Pico projectors: remember them? They were all the rage before everyone moved on to tablets and 3DTVs. A little late to the game, but Toshiba's two pico projectors are svelte models with a only storage and connection keeping them apart.
The Lumileo P100 weighs 96g (crucial when this is very much an additional gadget and you're already weighed down with other kit), and projects images at VGA (640 x 480) resolution at up to 150cm diagonally, from distances up to 65-inches. It has a 200:1 contrast and 14 lumens, and if you look closely you'll actually see there's a 0.5W stereo speaker included, too.
On the other hand, the Lumileo M200 is more hefty at 150g, with that extra weight dedicated to storing 2GB of inbuilt memory, a memory card slot, and stereo headphone jack. It can be used as a remote control, and actually has MS Office Viewer built-in, so would be handy for those meetings where you simply must show someone a Word, PowerPoint or Excel document.
Unfortunately, the M200 doesn't project any better image resolution (just VGA), but the diagonal size is increased slightly, to 152cm. Likewise, it can be used at a greater distance of 197cm.
Battery life isn't mentioned for the M200 nor the P100, but the M200 has a 1800mAh Li-ion, and the P100 a 1200 mAh Li-ion.
What it boils down to is price (it hasn't been mentioned) and whether you want something that has to be chained to a source such as a laptop (the P100), or want to be free as a daisy and projecting movies on the go (the M200). [Toshiba]