architecture goes, I prefer the Moorish style, but both Persian and Ottoman are really fascinating to me. If you are interested in Islamic architecture, you should check out this guys website, it is one of the best breakdowns and analysis of Islamic architecture I have ever seen... and its free. I found his discussion of geometry in Islamic design to be particularly fascinating. When I look at that type of stuff it really makes me think modern designers are lazy...

http://www.catnaps.org/islamic/islarch.html