Zac Barton has released Bolt, a Unity Dash like menu extension for Gnome Shell.
He describes it as:
A launcher thats a fusion of the Ubuntu dash, the Gnome-shell overview and the classic Gnome 2 menu which replaces the overview.
- Allows you to see recent apps, docs and downloads using Zeitgeist
- See applications in their categories - filtering made easy
- Search for apps, docs etc
- Blurs background
- Matches background color