I use XP for doing office works, entertainment, internet and hobbies.
I use Linux, currently Redhad 9(also required for work from home)
, and I have G5 for my sister and me.
When Time and Money matters,
G5 is cheapest (for the last 6 months).
Although timewise XP is the cheapest, but combined with the money I paid required for my hobby purposes(2 Video cards:GeForce 7800 GTX, All in Wonder ATIX800,SB X-Fi,7.1 speaker, 30inches Dell monitor, and all wireless network accessories, 480w power supply + tons of softwares + games, and tons of add in Hardwares, tablets)the window PC is a killer budget.
Moneywise, Linux is the least, but timewise it's a killer (research for the new drivers for new hardware, tweaking the software to behave properly).
Buit overall , I am most satisfied with XP, and I still couldn't figure out why some people said tivo is better. New tivo is coming, I will research that soon.

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