background patterns

http://www.fcukstar.com/ <--- that's just a gradient.
Now, you won't want to make a huge image in photoshop and slam it as a BG, because it'd be very big in file size, because you'd have to save it at full quality to get that smooth gradient.
But on http://www.fcukstar.com/ the whole background is in flash, and that doesn't weigh in size in the same way as bitmap images would.

The first one is just a clever pattern.