I bought a Netgear travel router for $10 some two years ago on-sale at a computer store I happened to be in. Simple to use, to understand, to connect to. Left it on one of my summer travels and couldn't find the same router for less than $40 anywhere. So I ended up buying a smaller Linksys WRT54G S travel router.

Both these routers are specifically intended for plugging into a hotel room connection and letting one or a handful of users access the internet wirelessly. I'm not sure how useful my experience will be because I don't know if these are even sold these days. But any replacement models will surely have the same create-an-instant-wireless-network capability for adhoc business meetings.

I can't say as to how I've had any trouble with the Linksys travel router, but it has always run very hot and is a tad more complicated to set up than the Netgear was. Btw, I almost always kept each router set to single-user as a security precaution, but never had any difficulty switching to multi-user mode.