eshoppes as blaxsun mentioned, and cpr. the cpr brand has a newer model out that comes with a siphon pumpa, but i cant say that ive ever been in danger of actually having a siphon full break on me anyway. even when i do a water channge, ive never had a siphon that was just sitting there, actually break.
ive heard the eshoppes type is a bit more difficult to get siphoned because of the bend in the siphon tube that you have to deal with whereas the cpr has an inlet on top that you attach a rubber hose to, to start your siphon.
when i compare the two, i feel that the eshoppes version might work better, but im just guessing, as i have not personally compared the two operationally, and have only used the cpr brand myself