Seat wise I like this the most;
Odyssey MX seat: I like this seat becuase it retains the looks of xc racing seats, while still maintaining comfort, strength etc. It is also pretty cheap at £20.
But, some people prefer this seat, I like them both;
Shadow Conspiracy Slim seat: This seat is a bit more bmx style, but still sleek etc. It is also a bargain at £22. You can also get different coloured stitching...which is nice.
Overall those are generally cheap seats, but if you want to go for a bit of big pimpin' try out a Macneil Seat and Post combo with a Macneil SL seat. Its super light, but pretty expensive for what it is.