Yup, I'll second the Rhythm Tech. I just got mine less than two weeks ago. I have mine mounted on my hi-hat stand, just below and to the left of my hats. I'm not quite certain that feels comfortable. I've tried on the to mount it on the hi-hat rod, but not for every song. Where else do others place their mounted tambourines?
I also use a Rhythm Tech tamborine, which is mounted on a Tama multi clamp and "L" bar. It gets clamped to either my hi hat base, or tom stand, depending on how much stage room is available. I've had this one for about 15 years...seems to be super tough, and it takes a beating on most gigs. Cutting,loud, and durable. Definately recommended if you play a lot of top 40/pop stuff.