Add widgets to a campaign through the marketplace?

I was thinking that I would love to have an hourglass to hurry players up when they're taking their actions, but I wasn't sure of any great way to add it to the existing UI. I'm sure that there are a number of similar niche tools that would be very useful for a minority of players. Although I'm sure that implementing a widget marketplace would be a real technological feat, it could be a real boon to the community.

I believe someone has already created an API script that did something like this. You might want to check with the API forum.