Sidebarry
A desktop sidebar. Yes, the novelty is killing you.
It's not illegal to have a fetish for Windows Longhorn. Okay, maybe it's a little sketchy to like Plex, and I am ashamed to know that there are people that like Aero (maybe it's just trauma from Luna?) but the sidebar was hot stuff. As such, a lot of my UI mockups orbited around some mechanism involving a combination of an Apple-y top bar and a Microsoft-y side bar.
Cmdsys had originally included a simple sidebar that just displayed a page in IE within it1 but the prospects for this were less than enticing. So after some deliberation I voted to rewrite it.
Footnotes
1 It actually included a single-page web server in case this involved cool javascript that was somehow more trustworthy when it wasn't being run from the file system directly)