OLPC as a terminal for NX, XDMCP, VNC, RDP, Citrix
Many schools have existing LTSP (uses XDMCP) or Windows terminal servers. Why not allow OLPC to connect into these to allow running of existing educational software, while not changing the way OLPC works. This will also allow older children who might find OLPC's hardware and built-in software restrictive to use OLPC to use OLPC as a portable personal and social laptop, while using conventional applications which require much more powerful hardware at school or university.
This would be achieved by adding NX, RDF, Citrix, VNC and X remote display client software to that installed on OLPC. (NX protocol would be preferrable because it is free and has the lowest bandwidth requirements).
The OLPC would be used as usual, except that you can connect to an access point wirelessly and then log into the server and run a remote session on the server at the same time as other things on OLPC. The NX, RDF, Citrix, VNC and X client software which displays the remote screen on the OLPC runs as just another application on OLPC.
It would be nice if services allowing NX, RDF, Citrix, VNC and X remote display could be automatically detected and by the OLPC, and show up as a remote session icon on the OLPC.
This idea has a lot of plusses, and no minuses.