Here's an intriguing and impressive bit of kit for what some people call the 'guerrilla pitch', where you take advantage of even the most unexpected opportunity to show your wares and sell your services.
The pint-sized Acer C20 'pico projector' ($349 from acer.com.au) from Acer hooks up to your laptop or smartphone using standard USB and HDMI ports to run a slideshow suitable for a small meeting, with the image cast onto any nearby wall at up to 168cm.
If you don't want to count on there being a nice white wall just where you want it, Acer also offers a compact 15 inch screen for $49.
It naturally helps if you can get the room as dark as possible but the C20 still has enough punch to do the job in a well-lit office environment. The inbuilt battery lasts for 'up to 2 hours', according to Acer, but we'd suggest you play it safe and recharge it after each presentation.
(And if you really want to travel light you could forego the laptop or smartphone altogether and load your presentation up onto a USB flash drive or a digital SD memory card, as the C20 has slots for both devices.)