[k__]

.de.su would be THE otaku tld, lol

[ThinkingGuy]

My first thought is that this TLD would be great for Japanese-language domain hacks, i.e., "i.ta.da.ki.ma.su" for a food- or cooking-related site.

(I just checked; sure enough someone's thought to register that one)

[naoru]

My email hosts on @desude.su domain :)

That's a private Google Apps deploy with about 5 users.

[TazeTSchnitzel]

.moe exists already ;)

[ohithereyou]

pant.su used to exist