You can jailbreak using any computer, it's still synced to your computer. I used an XP tower that rarely gets used to jailbreak mine. I use my Macbook for everything else though
I'm ready to jailbreak as soon as I figure out if I can keep my warranty after jailbreaking with limera1n, or else I'll have to wait for a jailbreak that lets me restore and keep my warranty.
According to Apple jailbreaking voids your warranty. However, it's easy to get around this by simply restoring before taking your iDevice in as Apple can't tell if you've jailbroken before in that case. Very few people get stuck in the position of not being able to restore to stock firmware.