Most will be a bit large for pocket carry unless you can stand it up along one edge.

If you decide to go with carrying it in your briefcase, I'd recommend the Victorinox Spirit or a Leatherman that can use the old style bit adapter. IIRC they use standard 1/4" hex bits. The new style uses a proprietary shaped bit.

Both Leatherman and Gerber have smaller models. The Squirts are about the same size as the KISS. They don't have pocket clips but do have a ring for attaching to a keyring.