I wrote many lines of Tcl back in the early .com days, as we had an in-house server stack based on Apache, similar in certain ways to AOL Server, but doing ORM stuff people only discovered a decade later with Ruby on Rails.
Only used a few times later to script Websphere via Jacl.
However, nowadays I don't have any reason to touch it as well.
Everything is a string is a bit quirky, but it's just lisp-like enough to allow you to do some really nifty things.
I don't ever want to write anything seriously in it again though, and I can't see myself starting a new project with it.