My current setup is a 10D body, a 50/1.4, a 28/1.8, and the 18-55 kit lens.
The 50/1.4 is by far the best lens. It's wickedly sharp, fast, and lightweight. It was my favorite lens back when I was using film. It'd still be my favorite lens if not for the fact that the crop factor turns it into a short telephoto.
I bought the 28 because I wanted a more normal prime lens. It's not quite as sharp or as fast as the 50mm, but it's still a good lens.
I bought the 18-55 and hacked it up to fit my 10D because that was the cheapest way to get wide angle coverage. It has proven to be surprisingly good for a cheap kit lens. It's noticably better than the film body kit lenses. It's as good as the nicer 28-105 ans 28-135 lenses.
If I were starting out fresh to build a new system, I'd buy a Rebel XTi body with the kit lens. I'd add a fast normal prime lens as my "go-to" lens, probably a 35/1.4L. The kit lens would be reserved for times when I absolutely needed wide angle or telephoto.
Don't forget to consider the 17-55/2.8 IS lens. It's pricey, but its optics are L quality, it's fast, and it covers everything from wide angle to normal to short telephoto.