yeah of course that's true about joomla... but you would have to weigh the cost of rolling your own booking system, could be a lot of work. some of those components already have advanced forms, calendar selectors, payment integration etc..;   @Marco - you sort of answered your own question - the first link uses http://www.opentable.com/ and the 2nd is a wordpress plugin; but there are some others on codecanyon that look standalone: http://codecanyon.net/item/booking-system/full_screen_p