[CentOS] Thin client system for X applications?

We're looking for what, years ago, I'd describe a s a X terminal --
something small, simple (and ideally cheap) that a user could display
X applications on.  I guess they're now called thin clients, but they
now seem geared as seats on the web, and for this application we would
need to be able display the results of running a homebrewed X
application from a CentOS system, either through xdm, or ssh with X
forwarding, or vnc.   Running CentOS too on the thin client would be
nice, but not a requirement.  The HP t5545 looks right for size and
price, but I can't tell if it could support displaying arbitrary X
apps.