Altec Lansing already offered a single housing monaural speaker in its Orbit line of portable speakers. But now it's doubled up with the latest model, the Orbit Stereo--a pair of USB-powered speakers that snap together into one long tube when not in use, so you can tuck them into a suitcase or laptop bag.
While the IML247 Orbit Stereo speakers aren't tiny, they are fairly lightweight, weighing 12.8 ounces, and you don't have to carry around any sort of extra power adapter. They also cost an affordable $49.99, which is $15 to $30 more than what you'd pay for the mono Orbit USB speakers.
If you're looking for something truly compact that sounds OK and puts out more sound than your typical laptop speakers, those single-speaker USB Orbits may be your better bet. But if you want a bit more punch to your presentations (or travel entertainment) and true stereo for watching movies or music in your hotel room (or wherever), the Orbit Stereo is the way to go.