Multiple browser versions on same computer?

Anyone know of a way to achieve this? I know IE is pretty much impossible, but what about Firefox and Chrome?

An idea I had is to get all the file installs from oldapps, then write a script and have it as a GPO that runs on first login, that copies all these browsers to the user.

Is there a better way that anyone knows of?

Thanks,

It might be simpler to have IE9 on the W7 host and IE8 published to the desktop of W7 via XP mode.

IE isn't so much of an issue as we have multiple resource machines (Win 7 and XP), so we just turn off IE updating and leave them.