Hmmmm, this isn't that cheap, but the Canon Canoscan 8000F is pretty good, I have no link, but IIRC it is somewhere around £90-110, although I picked up a display unit for £45

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Here is one of the first things scanned in, as part of it was needed for an RPG...
This is on it's lowest quality setting, and then being compressed into a JPEG of less than half the file size.
The quality of pictures scanned in is absolutely amazing, I scanned in some old photos and they looked perfect, I then printed them on my new printer and it was nigh on impossible to tell the difference. Sadly though, I no longer have those pictures on my PC.
Also, if you need it, it has a negative scanner.
Although I am yet to test it, my school's photpgraphy department has the model down from my scanner and the scans are very good, though bested by the single role negative scanner.
But it all depends on your price range, unless you want to look on eBay or find one like I did.