Out started off as an exclusively British site aimed at men only. Now there are branches of Out in other English speaking countries, although there is a strictly British side to it. Originally free, you are now expected to buy a licence at reasonable rates once your 30-day trial has expired. If you don't pay the licence, you get plagued by pestering notices. But it's not as if the licence is expensive, and you do get your money's worth. And Out is just -- well, so much nicer than the others!
Even better, there seems to be quite a large community of men from Nottingham who use the site, and who occasionally have meet-ups in Nottingham scene venues.
Gay.com has everything. It has some extremely cruisy chatrooms (which give rise to the extremely unofficial nickname slag.com), personal ads, forums, the lot. It's free, popular, and seems only really to work with Netscape. The content here is geared for men and women, but doesn't seem to overlap much.
This site started out life as a purely personals website, but has subsequently added content in addition. You can place a personal ad for free and once you have done so, you can search all the other personal ads by a number of criteria. There is apparently a fee if you start getting too popular.