@cheve : It actually has comments already and you can use them for prices - in the example above 'potatoes' has the note 'baking'

I've been asked about more price functionality before too; could you describe how you think it would work? How they'd be displayed and kept up-to-date?

I'm honestly happy to give features like this a go if people can help figure out how to make it fit.
Also what are you trying to achieve? Are you tracking cost variation over time?
Or is it comparison to different stores? (how do you get meaningful prices?)

One thing I can see being useful is a big 'notes' field that you get to from the edit bar; that could be useful for tracking info about 'research shopping' I guess.
Then a way to view an expanded list including the notes....