How do I calibrate my computer monitor?

Geometry issues have been taking care of easily through the monitor's built-in menu, but I would like to calibrate my monitor further, as I have done with my telivision. Colors in DVD movie's and regular videos look a bit washed out, and all such material look MUCH better when viewed on my calibrated Telivision via video out (s-video) on my Radeon DDR VIVO. Now how would I go about calibrating my monitor? This isn't like my TV where I have an easy intuitive menu layed out for me... the lack of Sharpness, Hue and Color settings makes it more difficult to do it through my Avia or Video Essentials DVDs. Is there some kind of software I can use?


BTW, I have a 19" perfect-flat Dell Trinitron and a 21" almost flat Dell Trinitron (no dual-display, just two different setups), both on WinXP Pro systems and using a 64MB DDR Radeon VIVO.