mtnbkr:
I have used Exceed as both desktop emulator & as a xterm generator...and as a few other things. Most times, it does alright.
Unfotunately, even Exceed can not overcome network lag for some apps, especially some moderately-graphics intensive apps. Sometimes, there is no substitute for running X locally. Note: Exceed may very well be up to the task & it could be the fault of the several routers my connection must navigate. It really doesn't matter to me, the end-user, though. Either way, runing over the network is too cumbersome.
I currently work 4 different projects that have four different labs. Lab-hopping to get something to run locally is starting to get old.