Just a few choice ones:
Clarions to Reduce Weeks, Team Up with SyFy, and Engage in Cage Fighting (see Kelly Link swear like sailor) – by a certain squid…
Mashups, Including My Forthcoming War and Peace/Alien-Pred Novel (and more fool linkage in the sidebar)
NASA, Ahem, Humor About Astronaut’s Head (oh dem NASA peeps, they cracks me up)
Academic Publisher Humor (oh–stop, stop; yer killin’ me here…SPEW? Reeeally?)
Cheryl Morgan has links to some here, as well.
And, finally, a few of the more obscure ones: