With gnome-do I could! It's very very useful for me, because tomboy is well integrated in Ubuntu. Why doesn't dash have anything about this?
I've written a small Lens for Unity, allowing to search and open Tomboy notes.
You'll find it here:
Please let me know if you find it useful or have any comments/problems.
Source -> here
As far as I can tell, no.
This question is related to a question I asked: How do I get Synapse to search my Tomboy notes? -- because both dash and synapse use zeitgeist. I am now able to search my notes with synapse, but for some reason not with the dash. I am not a developer, so can't say why not, but it is probably trivial enough to get Dash to show the tomboy notes logged by zeitgeist.
However, even if tomboy notes are logged by zeitgeist, this will not replace gnome-do: gnome-do searches through all your notes, whereas zeitgeist only logs the notes you open. I still rely on gnome-do just to search my notes.
I have posted a question that might bring us an answer: Tomboy notes logged by zeitgeist do not appear in the Unity dash. Why not?
Unfortunately, the Tomboy lens that was available in 11.10 doesn't work with 12.04. Fortunately, Tomboy notes can easily be searched using the HUD: press 'Alt' + a keyword or title of yor note... et voilà!