I have two domains - a .com and a .org.uk . Neither is specifically Amiga related but I am planning to add Amiga content on one of them. As pretty much all bases are covered it will probably be rehashed stuff! (I pay approx £10 a year for each and have unlimited e-mail addresses on each [theoretically, obviously; I don't know the limit but have 20 on one of them]. Using MySQL and so forth costs a little extra.
Looking at the subject again, are you wondering about people owning domains containg the word "Amiga"? There must be a few here surely... Do you own any others yourself?