ultravnc(uvnc)

using 1.0.9.0 beta, no big problem at all
and some small tricks here,
it is default to send win-key , alt-tab , ctrl-space to the machine running the viewer (vnc client)
to make it send to the host (machine running the vnc server) directly, activate the scroll lock
then it will work like a charm
it is quite useful for Asian user to switch input locale between English and c/j/k

and in vnc, I mean the Realvnc, I need F8+l to make the Ctrl down and hit space and F8-l again to release the Ctrl >_<
although Realvnc uses latest rfb 3.8 (current vnc version is 4.5.4) , it doesn't make it much better , but I love its DisplayDevice setting, I make it to \\.\Display1 for my primary monitor, while uvnc connects to all monitor first. And seamless file transfer in Realvnc is marvelous.

to save bandwidth, ssh / telnet is a good choice, but it is only text mode.
I use the tight encoding in uvnc, full colors, zip 9,  quality 0, it is good on my dsl line, with acceptable speed and responsiveness. And zrle in realvnc will make the session always loading / freezing

looking forward to uvnc2.0