There is a shit tonne of stuff out there with promises of increasing your productivity. Apart from looking like they have been designed by the same person for an audience made up of Hyperopia+ADHD sufferers, they do seem to have one thing in common - shit's easy when you know how to cheat.
Most of these sites are guides or a set of rules by which, if you abide by, should allow you to work better; do you job better, technically. The examples I'm going to list in a minute will mostly only apply to graphic/web designers and maybe some web developers. I don't use any of them at all so I can't vouch for them but I found them via my usual channels of proactive users from previous industries and they are totally legit. It is good practise to keep all of your fingers in all the pies.
One particular thing I found out from trawling through the realms of the digital creative industry on this here internets - look at all those buzzwords; somebody hand me a dictonary, please. They keep renaming things to sound more technical and official. There's probably an app for that out there, anybody?
So anyways, here they are in no particular order.
http://photoshopetiquette.com/ - I thought this was very useful for web designers particularly. From previous jobs, working as a web developer was horrendous if you were paired with a web designer who cared little for the "technical" side of things. More so when they were previously print-based and so, had no clue that rounding off a pixel did not literally mean 14.25 pixels to 14.3 pixels.
http://froont.com/ - Design websites directly in the browser with a simple drag and drop interface - Remember Dreamweaver? I try not to. Of course, this is nothing like Dreamweaver. It just reminded me of it, for some reason.
http://icomoon.io/ and
http://fontello.com/ - Custom Built and Crisp Icon Fonts, Done Right - Best used to offset that whole "wall of text" problem. I don't really subscribe to this trend but I do have a completely different approach to the same problem - it mostly comes down to K.I.S.S.
http://html.fwpolice.com/css/ - CSS Beautifier - Yeah, see, beauty is definitely in the eye of the beholder. Look at all that wasted white space after the cosmetic surgery where previously, it only took up one line!
https://slid.es/ - This might prove to be useful for future talks and impromptu presentations for sure. I just wish there was a way you could share the slide with everyone in the room and then remotely control what they are seeing on their screens whilst you present. Also, please to be adding a key press for next slide, thanks.
http://paperkit.net/ - Printable graph paper template - If I had access to unlimited printing privileges, this would be something I abuse.
http://redpen.io/ - Upload your design and get live, annotated feedback superfast - It's like a private imgur, if that makes sense. I do like the personal touches and the straightforward simplicity of it all - "Hey guys, I made this and want opinions that you can all post and see. Are we done? Thanks, I'm deleting this now!"
http://flatuicolors.com/ - Ridiculously exaggerated way of getting some colours copied on to your clipboard. It uses flash!
http://adamwhitcroft.com/wirekit/ - A bunch of Photoshop shape layers to make wireframing your next iPhone app just a little easier. - Apparently does what it says on the tin. There's that term - wireframing. Only for iPhone, I'm afraid.
http://www.uxapprentice.com/ - More wireframing! This one comes with quizzes to make sure you're actually reading what they wrote except it becomes clear soon enough that the right answers to each of these questions are usually the most ironic. Soon you'll be accosted with phrases such as - Ranking: You're awesome. You've mastered this phase. I'm guessing this would be useful when it comes to justifying that bill to your clients.
http://cssglue.com/cubic - Visualize and manipulate CSS transition functions - This should be interesting, if it worked?!
http://www.unheap.com/ - A tidy repository of jQuery plugins - Firstly, really appreciate the thumbnails for each plugin but are they mostly "designed" by one person? Just wondering as that's probably a dream job for me; akin to book cover illustration. Finally, thank you! This will prove to be very useful if I decide to use it.
And there ends my adventures in the old, booming digital creative part of the internets. Maybe it's been useful for you.
Update:
I keep finding new crap to add to this list and depending on how long these sites last (sites die all the time, folks!) and when you're reading this post, some of these methods may well be "deprecated".
http://codepen.io/ - CodePen is a playground for the front end side of the web. It's all about inspiration, education, and sharing. - Seriously experimental web stuff over here. May break your browser.
http://tridiv.com/ - Tridiv is a web-based editor for creating 3D shapes in CSS. - I think this speaks for itself. I mean, uses for such things come up as nil in my head. I'd prefer an exporter for Blender or svg elements to appear on the web, that would be spiffy.
http://css-tricks.com/examples/ShapesOfCSS/ - All of the below use only a single HTML element. Any kind of CSS goes, as long as it's supported in at least one browser. - This was so "trendy" in 2011. But even then, who uses these things? Meh.
http://www.patternify.com/ - Patterns, really? In this day and age? Well, yeah and unlike most "generators", this one uses base64 code so it's purely CSS. Also, did I mention it's an editor?
https://www.iconfinder.com/ - A massive library of icons, most of which is eww but I'd be hard pressed to say they weren't used at all. Gosh, graphic design is so ugly.
http://sidebar.io/ - The best design links, every day. - Made by the same dude who made that very useful pattern editor except this one is purely a curated site within his own taste and mostly, marketing spiel. Probably his buddies too.
http://mixture.io/ - Rapid prototyping, static site generation and so much more - Holy shit, my eyes. Also, I guess all the cool kids are using the .io extension now.
http://css-tricks.com/ - Everything you've always wanted to know about css but were too afraid to ask. Like jedi mind tricks but for the web. Actually, no, not at all. One of those things actually work.
http://www.shadycharacters.co.uk/ - The secret life of punctuation - This is more for me, really. Anything to do with type and print, my eyes will widen.
http://www.fudco.com/chip/deconstr.html - How To Deconstruct Almost Anything by Chip Morningstar - This ticks so many boxes. More of an amusing read on harsh truths.
http://stumpypencil.blogspot.co.uk/ - A blog for digital art tools, for Photoshop and other art software. - This was a lovely find and linked from other digital artists which, if you are one, will know the extreme limitations of art software when it comes to brush options, amongst other things. I use Gimp so this still applies to me lest you think it's entirely Photoshop based.
http://www.mobileinc.co.uk/2013/04/designers-making-moves-to-disrupt-recruitment-agencies/ - A particularly useful blogpost by an unknown designer.
http://prototypo.io/ - The font generator - I signed up for this some ages ago but have yet to hear anything from it. Putting it here to remind me that it exists.
http://greweb.me/2013/09/beez/ - This guy does amazing things with the web audio API.
http://www.wab.com/ - HTML5 demoscene.
http://plnkr.co/edit/LG20SL?p=preview - Another web audio API but I'm failing to list the practicalities of this due to the limitations of browser support.
http://embedmydata.com/ - Embedded MetaData Explorer - I'm a little paranoid about thing injecting crap into my stuff when I use online services like I've mentioned above so this keeps my sanity in check, somewhat.
http://gtmetrix.com/remove-unused-css.html - Does what it says on the tin.
http://www.fontwalk.de/ - What happens when print designers become web designers? All hell breaks loose and functionality gets left out in the rain.
http://www.ffmark.com/ - More of the same but with slightly more functionality thrown in for good measure (ie; no one was looking).