I wonder if there's a website where you can post your ideas for coding projects. I had a (very) brief search, but didn't find anything so far.
Various software ideas pop into my head from time to time.
Here's one of them:
Connecting people via a database correlating hobbies with people.
By chance I found out that a colleague read some of the same books as me - we had a bit of a chat about the books and it made a nice change to talking about work. I wondered how many other colleagues read the same books as me. So originally the database idea was just for work. Then I thought it could easily be expanded to allow people in local neighourhoods to find people with similar interests. Then I thought it could easily be expanded to be a global database.
The trouble would be getting people interested enough to fill in their details. Writing the database and the interface would be easy by comparison!