I've switched to using xfce4-appfinder as a replacement for xfrun4 recently. It's a pretty nice experience overall, even though I'm missing the ability to launch arbitrary commands like I could with xfrun4. So today I had an idea on how we could improve this: all we need is a custom tree model and a plugin infrastructure to allow plugins to be written as appfinder item providers. They could provide any kind of actions depending on the text typed in by the user. Here are two example mockups:

Implementing this should be relatively easy with a bit of experience in GTK+ and GLib. It's not as powerful as GNOME Do but it's also much more simple ... and useful, at least as far as I'm concerned.

Anyone up for the task? Maybe this could be one of the projects for next year's GSoC, should we decide to apply.