I've decided to start posting every idea for a site I have because otherwise I stew over them and never do them, and then hate myself for not having any time outside of work to build these things. I keep a list, you see, of every idea I have--dumb or not--and the date I came up with them. They usually aren't very good ideas, and if they are good, someone usually already does it.
So here is one I had a couple days ago when thinking about one of the difficult things about mailing stuff to people: I hate mailing stuff to people. I hate finding a box that fits, and wrapping the thing up so it doesn't break. I hate finding postage and of course tape suitable for mailing. Above all I hate going to the post office.
About a year ago, I had the idea of selling self-addresses stamped padded envelopes. You would go to a site and enter your address, your friend's address, pay a little bit of money and then your friend is mailed a padded envelope containing a padded envelope that is addressed to you with postage paid. Your friend simply inserts whatever he was sending you, tapes it up, and drops it in the mail. So, a year on I realized there could be a whole online store where people enter stuff for sale and enter the size and weight (I'm told eBay lets you type in UPC #'s and it figures out the size and weight for you by using magic).
I think it'd work best for video games, as they have the best cost/size/weight ratio. So if I was starting it I'd focus only on video games as they would all fit nicely in a padded envelope.
Though Amazon has the infinitely cool S3, I still think my idea of web storage has a spot somewhere. The entire idea could be deployed on S3, but I think the authorization would be a sticking point, and I'd prefer to not require apps to register with Amazon. I still want to do that one.
I have another idea that I think I'm going to hold onto for another week. It would probably take about a week to build properly, and it would solve the whole problem I have with sharing my Wii # or my phone # with friends. I was reminded of it after seeing Andy's link to this post by Simon Willison about whitelisting.