Just a few.......
Treewind My own site
Micro-Robotics my day job
Mary Humphreys and Anahata
Fendragon a ceilidh band
English Rebellion another ceilidh band
Ethel's cats another ceilidh band
Four Hand Band Mary and me playing ceilidhs as a duo
Pig Dyke Molly a dance team
Mayflower Folk Music an almost defunct club in Cambridge
Uveitis Information Group something my sister is involved in
Sutton Folk Club
Towan Cottage Holiday lets in Cornwall

"Do you maintain a section in yours where you practice tricks before making them publicly viewable?"
Mine are all created and viewable on my home computer, including server side stuff (there's a copy of apache running locally) so everything gets viewed and checked before uploading.

All hand coded PHP/HTML, and Pig Dyke uses a MySQL database, for the pictures and for a lot of stuff you can't see without logging in as a team member.

You'll be wishing you hadn't asked now...

Anahata