The Herd Of Kittens - "Them" Useful Tech

Database

postgresql and other databases are a possibility. Directories full of carefully-named files might be close enough in practice, though.

Storage

Storing the data as entire blobs might be a use for XML, though it might be better to just export to that. On the other hand, if the raw data is stored in a directly browsable way...

Input

use munpack, or some perl Mime parser, to split out attachments?

Is there some ss-like layer on top of tcl, for a simple olc-like client?