My team is using RTC (Rational Team Concert) with RAD/Eclipse...but I the minimalist development approach so I use Sublime to edit files...I would also like a slimmer RTC client than Eclipse. Is this possible? Are there any in existence?
You can use scm commands for the source control operations. On Windows,those same operations are available with the Windows Explorer (RTC4 only).
Coupled with the Web interface, which allows you most of the other operations (work items, queries, builds,...), you have a lightweight alternative.
However, it isn't directly integrated with a non-eclipse based IDE.
The other option, from a deleted answer from Seth Packham, is:
use the Windows Shell client available in Rational Team Concert 4.x. Learn about the Windows integration here with this video, or this YouTube video.
It basically integrates the source control into the Windows Explorer, like you might have done with SVN.