Nerdy
Unless you're at least this |<----------------------------------->| intelligent, these webcomics most probably won't make any sense to you. And even if they do, there's still a great chance you'll miss the point.
Buridanův geneticky modifikovaný osel
Nerdy. Most probably you won't make head nor tail of it, as it's in Czech. There are a few strips translated to English, so feel free to give it a try. [detailed info]
Author: Jojin&HedgeHog
Updates: Random
Website: www.bugemos.com
Saturday Morning Breakfast Cereal
Single-panel bowl of punch. Lines. [detailed info]
Author: Zach Weinersmith
Updates: Daily (Monday to Sunday)
Website: www.smbc-comics.com
xkcd
A webcomic of romance, sarcasm, math, and language. El Magnifico! [detailed info]
Author: Randall Munroe
Updates: Weekly (Monday, Wednesday, Friday)
Website: www.xkcd.com