Best 3 pound laptops?

Can anyone suggest which is the best "ultralight" laptop? I want something
around 3 pounds, if possible, and a biger screen is still better. Also
higher res and CD-RW. I know I might not get all of these.

A lot of people seem to think the IBM Thinkpad X-series (use X21, X31) or
new X40 are best. If you buy the IBM media slice I gather you've got the
built in CD possibility.

But are there other units as good as these at the same price point?
For new ones I'm trying to keep it at $1500
For used, $1000 or below.

Thanks