Sparrington
Hee. Hee hee. I have next to no sense of humor when it comes to portmanteaux, but I have to confess that this one makes me laugh.
I have no idea why Spike/Xander people have embraced "Spander" because that's just fugly. Plus, every time I hear "Snarry" (which seems to be a largely accepted term in the Snape/Harry part of the HP fandom), I want to bash someone's head in.
"snarry" sounds like an unflattering adjective.
"Oh, my god, get away from me! You're all snarry!"
I was going to mention Clitney ( the first time I saw it used was for Clark/Lex/Whitney thought). Also Spillow for Spike/Willow.
I think Sheppard/Weir got dubbed Sparky at some point.
BATMAN WOULD NEVER SLEEP WITH XANDER!!! And Xander would never be able to get it up in that scenario.
I was always... fond? of Spred. (Spike/Fred)