I'd like to travel from Jerusalem to St Catherine's momnastery in a single day. It appears that a 07:00 bus from Jerusalem could get me to Eilat by 12:00; that from there, a bus/taxi could get me to the Egyptian border at Taba; Taba to Dahab by bus, 2 hours, and the 17:00 Bedouin Bus fron Dahab to St Catherine's before nightfall. Great, in theory: but how practical is this? Has anyone else tried it?
I recently did Beer Sheva to Nuweiba in a fairly easy day, I think its possible, there are plenty of cheap beach camps and taxis if things go wrong.
http://www.lonelyplanet.com/thorntree/thread.jspa?threadID=2294891

No, it's not realistic. Expect delays at the border, in the Israeli bus, in the Egyptian bus... Unless you're very lucky you won't make it.

I can’t imagine doing this but then I have spent three days at St. Catherine's Monastery Guesthouse so I could study in the library and the icon collection. IF you need to do it in one day and money is not an issue, I would suggest you contact a reliable travel agent in Jerusalem I found this company http://www.tourplanisrael.com/?CategoryID=227&ArticleID=222&Page=1 on the Internet. I have no connection with this company and it is just an example that it can be done.