1) You will always have an outdated installation disc so whenever you want to do a install you're stuck with hours of system updates.

2) Losing your install disc means your SOL.

3) The activation process is not always painless. Whenever you have to call their activation line you are wasting time.

However, when you get on the wrong side of it, it is a pain in the ass of Lovecraftian proportions. I don't know if it's my luck, choice in hardware, or what, but I've had perfectly valid (retail!) keys start throwing WGA errors after working fine for a few months. After spending literally hours on the phone with someone who speaks broken english, I took my crippled XP install (this was back in the pre service-pack 2 days where failing activation meant you got locked out after a few minutes), went to a torrent site, and downloaded an activator.

2 hours (spent on the phone in a fruitless endeavor with the best of Indian tech support) and 5 minutes (spent downloading and running a crack) later, I finally was able to use my bought and paid for software.

After that, I pulled down an ISO with the service packs and cracks and other goodies slipstreamed in (XP Ultimate Edition by Johnny, still exists out there somewhere), burned it to a disc, and haven't used "legitimate" channels since.

Microsoft does not have my permission to use my CPU cycles and power to inflate their antipiracy metrics.

I wont say which program is it because I do not condone piracy, but it is widespread in the internet.

I agree that Microsoft should remove all anti-piracy stuff in their products. It only makes their products more expensive.