Just checked my top referrers across all domains that I use/used for freesites and have the following in no particular order:
L O R
Link For Sex
Hoes
Richards Realm
Smut Gremlins
Penisbot
Freesitexxx.com
Danger Dave
Freepicssex.com
I know... more than 5... but depending on the niche, some sent more traffic than others so didn't want to leave them out. Oh and the first site in my sig is in there
Lisa