I do that with my video card... I can hook my video card to my tv with a port on the back of it. I have a wireless mouse and keyboard and tada I can surf the net and play games on my tv. It does not cost too much well it depands what you think costing an arm and a leg. It is a few years old it cost like 500 bucks when it was new you can probubly get it for 200 bucks now...
CPU Type: DualCore AMD Athlon 64 X2, 2200 MHz (11 x 200) 4200+
Motherboard Name: Asus A8R-MVP (3 PCI, 1 PCI-E x1, 2 PCI-E x16, 4 DDR DIMM, Audio, Gigabit LAN, IEEE-1394)
Video Adapter: ATI Radeon X1800 XT (512 MB)
Audio Adapter: Analog Devices AD1986A @ ULi/ALi M5461 High Definition Audio Controller
Disk Drives:ST330062 2AS SCSI Disk Device (320 GB, 7200 RPM, SATA-II) x4 (1280GB)
Network Adapter: Marvell Yukon 88E8001/8003/8010 PCI Gigabit Ethernet Controller