Ahem.
Check the Archival Info forum for some popular options:
t-bars,
shockmounts,
clamps.
Some of the common taper online retailers: Masterpiece AV, Sonic Sense, Oade Bros, Cascade Media. Or check your local music equipment supply store.
Clamps are useful in all sorts of situations - balconies, other tapers' stands, tables, stage lips, chairs, etc. IMO, all tapers should have at least 1 clamp.