Labels have become a common staple for DWRPers; they're handy for sorting out your inbox, and lets those of us who enjoy color-coding turn our inboxes into awesome rainbows. But Gmail only provides us with a very limited palette—haven't you ever wished you could choose any color you wanted? Well, turns out, you can!
1. If you have
Firefox, download
Firebug. It's a useful add-on that lets you easily edit the HTML of any page to your liking! Chrome has this functionality built into the browser, so its users don't need to download anything extra.
2. Go to your Gmail account. On the label sidebar, click on the colored square of the label you want to change, then click on "Add custom color" to open the palette.
3. Choose any color to affix to your label; it doesn't matter which one, since it won't be your final label color. Then, right-click the square and click "Inspect Element with Firebug" ("Inspect element" for Chrome).
4. Don't be alarmed by all the coding that shows up! Just focus on the right frame. Find the part that says
background-color: #000000; (where "000000" is the hex color of the color you're editing), then fill in your desired hex color code and hit enter. Then, click on "Minimize Firebug" (but not "Deactivate Firebug for This Site"! Chrome users, just click the X).
5. Aaand... you're done! Click the new color in the palette and apply as usual. Have fun making your inbox a rainbow!
If you need a little help with step 4, here's a visual reference:



Disclaimer: I actually didn't come up with this on my own, because I am sadly not that smart; when in doubt, Googling always solves your problems.