there are several options for using XP as host and mini-rdp terminals. the people at ncomputing are best known for that though there are people in Israel as well as Canada with same solutions. The ncomputing people also support Ubuntu so that is liability-free option.
The liability being that none of the are officially covered/sanctioned in the MS Eula and technically they could come back at some time and demand compensation. Having said that MS seems to like the ncomputing guys and obviously needs toolset to battle Linux (no help from Vista there).
I did an eval of ncomputing up on my blogger at thinclient.org that might be helpful plus some other options.
On the ncomputing side the x300s are much faster than the L-series.
Craig
http://www.thinclient.org
