Try a used T40, T41 or T42 -- maybe a bit on the bulky side for you, but they have really solid hardware support under Linux / BSD (eg suspend resume usually works with no fiddling, wireless works, etc). These were the last decent models in the original IBM Thinkpad line. For some reason the T43, the final T-series model which predates Lenovo, is much flakier than its predecessors.