xkcd.com: A webcomic of romance and math humor.

Extended NFPA Hazard Diamond
With most labs, the hushed horror stories are about something like dimethylmercury or prions, but occasionally you'll get a weird lab where it's about the soda machine or the drop ceiling.

Roman Numerals
100he100k out th1s 1nno5at4e str1ng en100o501ng 15e been 500e5e50op1ng! 1t's 6rtua100y perfe100t! ...hang on, what's a "virtuacy"?

What If? 2 Countdown
If you don't end the 99 Bottles of Beer recursion at N=0 it just becomes The Other Song That Never Ends.

Superintelligent AIs
Your scientists were so preoccupied with whether or not they should, they didn't stop to think if they could.