Certainly like my Quassel.  While I don’t have time to post about the awesomeness (and the downsides against command-line-junkies-dream IRSSI), I do require my theme to be online/available.

https://www.darrennolan.com/wp-content/uploads/2010/05/jussi01-darktheme.qss

Based on Jussi’s Darktheme (on the Quassel website) but a tad easier color contrasts in the main text area and back to default-ish colors in the nickname and chat-lists.

Edit:  Bit of an after though, the font is Consolas (between 10pt and 12pt is nice) – typically MS font.