I have an older Coolscan 4000 by Nikon, the new one is the Coolscan 5000, which uses USB2 instead of firewire and is a bit faster, I think. Nikon's Site
. I used to use only slide film, and doing a 16 pass multi sample scan at 4000 by 6000 pixels let me make an amazingly clear 20"x30" print. It's pricier, though, I think it was about $1000 or so.
But, it's totally worth it. Mine does 12bit color per channel, I think the new one is 16bits per channel. Nikon's DigitalICE automatically corrects dusts, scratches and whatnot, and saves a LOT of time later.
The Nikon is a slide/film scanner ONLY, no flatbed for prints. But, that's how you get a much higher resolution and color sampling.