remote access

looking for simple and easy romote program to access computers over the internet in order to give support, maintanance, repair ect. like i am seating in front of the computer.
supoort XP, 2K, W98. all pcs using ADSL/DSL, no server involved. pcs are connected directly to adsl modem
or via router or peer to reer (few pcs connected to the internet via one pc)
thank you for your help in advance