Is the Raspberry Pi good as a graphical thin-client ?
Is the Raspberry Pi strong enough to run remote X sessions or do stuff like Xmove to share remote X apps?
Personal experience tells me it's pretty excellent. I have used X-forwarding over SSH and it performs well, as if executing natively. I've had multiple forwarded windows on the go at once, including Eclipse and Chromium.
I've also played with forwarding mouse and keyboard using from my desktop to the Pi using
x2x which works by using the Pi X session as a second desktop to the existing session. I guess that's similar to
xmove, which I havent used, but will look into.
With this setup I have had Eclipse open on my Pi Screen, forwarded from my desktop PC. I then controlled the mouse and keyboard of the Pi using my netbook with
x2x. Thus I was typing code on my Desktop using my netbook keyboard, using the Pi to view the results.
Hope that helps somewhat.
If you got here because of the question's title (how do I use the Pi as a thin client) rather than the question's content (how does it perform as a thin client), it's probably worth having a look at the RPITC (Raspberry Pi Thin Client) project:
It comes with a choice of clients (VMWare View, RDP, Citrix, X2Go, ...). I've only used it for RDP so far (RDesktop and XFreeRDP), performance there is more than satisfactory.