I have used Margi's Presenter-to-Go, available at
www.margi.com for $199. They provide a compact flash card, cable to connect to the projector, an IR remote that works great and software. The software places an icon in the regular powerpoint software that when clicked renders the presentation into the format that the pocket PC can understand. While the resolution is execellent, pictures come out with a modeled look.
From the axim, the user can hide/unhide and move slides. The Presenter-to-Go will not trigger media (play music, videos) or hyperlinks but works great otherwise. (Windows Media Player will play simultaneously with Presenter-to-Go.)
I used it twice a week for about six months now and have been extremely happy with it. It sure beats lugging the old laptop around for seminars and is a much quicker setup.
Good Luck!!