Our setup of LTSP for our office went off rather well. We have one P4 "server" that provides terminal sessions for 6 machines now and can easily support upto 20 odd terminals. Since our CRM system (SugarCRM) is web based and externally hosted, the employees needed no training to get to work. In fact a couple of them did not even realize that they were on linux.
1. Terminal Server: p4 1.8 G, 512 MB ram, 40x2 GB ide, FC4, LTSP (latest)
2. Nodes: p1, celerons et al, 64 MB ram, decent SVGA, PXE enabled ethernet
The total cost of providing 6 computing stations was so small that it is embarrassing to mention it :) We set it up in about 3 hours including tweaking the LTSP configuration and gettting the firewall settings right.