I have an old Artec 34 bit scanner that takes half a century to scan a letter size document. Don't even mention if I have to increase the resolution to lets say 300 then I will have to wait a full century for it to churn out something on my screen. Despite all of this it does its' job and so I cannot complain too much. I have not looked at modern scanners - what are some of the types out there today? How fast can it scan a full color photo and at how many bits?
I just started a new job last week in the archives department at school, and I love the scanner I'm working with. It's a Hewlett Packard Scanjet 4600 See-thru Flatbed Scanner. It's incredibly thin and cheap, but it's really good. One of the things I really like about it is that you can detach the top from the bottom, so if you're scanning something from a really thick book you aren't having to try to work around squeezing the book inside of it. Plus, the top is see-thru, so you can look down and see exactly what you're getting.
Scanner
Thank link has all the technical information and a picture.
I'm currently using an "all in one" HP printer, scanner, copier, fax machine. It's awesome! I couldn't even begin to tell you what the resolution is, but it will scan a full-color picture in less than 10 seconds. The only drawback is, it will not scan anything other than a flat original -- so, no books, etc. It's nice to have around.
This is a very loaded question as it is going to depend greatly on exactly how much money you would intend on spending. The basic consumer scanners will develop at something around 3200 x 6400 dpi. These start selling for around 100$ US and go up. The larger and more sophisticated scanners however start around 250$ US but scan at a resolution of 4800 x 9600 dpi.
*For those who wish to say, "Money is no option, I want the best" I warn you to be prepared. For 500$ US and up you can get a scanner that is capable of 6400 x 9600 dpi at the hardware level and up to 12800 x 12800 with software emulation. These scan at a depth of 48 bits for a quality possibly near or even better than the original being copied.
I will be the one to recommend Epson scanners above many others. They are generally a little more expensive but have fewer problems and more compatability with both PC and MAC.