best one I've used,
This review is from: Duronic SP400 Smart-Pointer (Red/Chrome) 2.4Ghz RF Wireless Presenter with Mouse Function and Laser Pointer + 2 Years Warrantee (Electronics)
I regularly give presentations and have tried many of these devices, although this is the first I have bought for myself. Anyone presenting from a PC should use one of these as it means that you are not punctuating your speech with trips to your laptop.
It installed first time (Windows XP), is very simple to use (with button placement that means you don't need to look at it every time), and has all the features you might need (forward, back, move in and out of presentation mode, blank screen, plus a laser light pointer). I also like the fact that it's red as you can spot it quickly if you put it down mid-presentation.
I am absolutely delighted with it.