This thread will be a collection of useful links/programs/etc that are in some way useful to those of us in the web development/design fields. Try to include a short summary or description of whatever tool it is you are posting, how it fits into your workflow, or anything else that might be of help. Who knows maybe this will have a sticky someday. Ill try to start off with a few of my favorite tools:
Emmet - http://emmet.io/
Plugin available for a lot of text editors that allows you to write shorthand code, then hit a key and expand it all out into perfectly spaced html like so http://prntscr.com/3j1nte It has a pretty steep learning curve, but once mastered makes you look like a wizard as you type one line of very long gibberish that expands out to a full html page. It took me almost 3 weeks of constant use before it started making me faster instead of slower. Take this, its dangerous to go alone - http://docs.emmet.io/cheat-sheet/
Lightshot - https://app.prntscr.com/en/index.html
Screenshot utility that auto uploads screenshots to prntscr.com (uses imgur) and gives you a link to it for sharing. Great for pointing out stuff rather than typing. Gives you some basic edit options before you upload, crop, text, arrows, etc. Very handy. Looks like this http://prntscr.com/52ufde
Renamer - http://www.den4b.com/?x=products&product=renamer
Rapid and easy renaming of multiple files/directories. Extremely powerful, tons of options for stripping/adding/replacing characters, accepts regular expressions if you have somthing really complex to do, and just all around a badass program to have. Got a massive collection of photos that need to go into a gallery? Hate the messy file names that come off the cameras? Solves all that.
Hex to RGBA - http://hex2rgba.devoth.com/
Just like it sounds. Converter for hex colors to RGB and RGBA with a quick copy button. I'm sure there are others but this is the one I like. Plain and simple to use.
DNS Propagation Checker - https://www.whatsmydns.net/
Useful for checking whether or not your most recent DNS change has propagated out to some of the big DNS servers.
DNS Health Checker - http://www.intodns.com/
Useful for diagnosing more evasive and annoying DNS issues with your sites. Best to just run it against your site for a better explanation of what it does.
Dreamweaver Password Decoder - https://www.supersneaky.ninja/tools/dreamweaver.php
Note: This is just an example of the of the tiny javascript function needed to decode the password hash found in Dreamweaver's STE files. Simply open an STE file, look for the pw="blah" and put blah into the decoder. If you wanna use this though, I suggest hosting it yourself! Pasting your FTP passwords into random sites on the internet is unhealthy. (That's my site, I promise not to harvest your passwords)
Website Copier - http://www.httrack.com/
Exactly what is sounds like. A program that goes to a site, follows all the links, and downloads all the assets. Useful when you have to migrate a site in a hurry, because a client pissed off the previous developer, and they are going to wipe the site off of their servers and a traditional migration is not possible. I may or may not know these things from experience.
Google Fonts - http://www.google.com/fonts
If you didn't know about these already, then you should. Because free fonts are good fonts, and good fonts are better than Comic Sans.
Privacy Policy Generator - http://www.generateprivacypolicy.com/
There are tons of these out there for ToS, privacy policy, refund policies, etc. Generally involve a short questionnaire and poof, copy paste your policy. Useful for el cheapo clients who can't/won't have someone write them a custom one. Obviously, after you generate it, you should read it and the client should read it to make sure everything fits.
I'm just going to breeze through the next few since they shouldn't need much explaining.
JSON Formatter/Validator - http://jsonformatter.curiousconcept.com/
Minify JS, CSS, HTML - http://compressmycode.com/
Unminify JS, CSS, HTML - http://unminify.com/
W3C Link Checker - http://validator.w3.org/checklink
Checks your site for broken links. Check out the other W3C tools as well, all handy stuff.
XML Sitemap Generator - https://www.xml-sitemaps.com/
Generates an XML sitemap (go figure). Pretty useful, this ones limited to 500 pages, maybe others that are not.
That's all I've got for now! Hopefully someone finds some of this stuff useful. Post up any tools you guys use.