"Connecting a laptop to two projectors" Topic

I'm overseeing the techie side of a presentation coming up, and I've hit a situation I've never handled before, though I know it's common. I have to run two projectors simultaneously from one laptop. Both projectors will be showing the same presentation, so that's good.
I know I can split the VGA signal using a VGA splitter. I've read this will degrade the image somewhat; I've also read that some laptops can't handle such a split.
Another option I've run across is to split a USB signal; is this possible? Is it necessary if the computer has two USB ports— that is, can the signal be sent out both ports, or do I have to use one port and a hub or splitter (is there a difference)? And if the projector has a remote, can that be used via USB to control the presentation, or will having two projectors mess this up?
I'm also wondering if it would be possible or better to connect one projector by VGA and the other by USB, and use one projectors remote to control the slideshow while the VGA connection simply mirrors the image. (That would save me having to buy a splitter…)

Thanks for any help or advice.

PS I think the computer in question will be a Mac running OSX (not Lion), but we'll have a PC handy if needed. (How the heck did I get stuck with this job? Oh, right. I volunteered. :-P)

kvm switch. treat the projector as monitors.

Also check your projectors. Ours have a VGA out to go to the second projector so they can be daisy chained.

Well whattayaknow— one of our projectors *does* have a VGA out port. Daisy chain, here we come.

Thanks guys!