Hmmm. Here's a problem that I'm going to end up building a solution to if someone else doesn't do it first (and by all means, please do it because I am lazy and have enough projects to last me for the foreseeable future): A CRUD application generator. You go to a page and define all of your models and basic rules. The models get defined in very simple terms - you give each model a name, and then define each field wit…
If you're willing to go without Python/Ruby, then a hosted Drupal (and it's trove of modules) is perfect for this. Acquia (which includes Drupal's founder) was founded to fill this space.
However, I'll definitely be checking it out for simple throwaway stuff.