Recently I found the blog of Peter Boehme and this post in particular was really interesting (aside from all his amazing artwork) http://peterboehme.blogspot.co.uk/2013/06/street-view-studies.html
A friend then also showed me the work of someone else on deviant art (http://mr--jack.deviantart.com/art/Geoguessr-I-379975044) who'd been playing a game called GeoGuesser, which dropped you in random locations around the world on google street view, where he would then paint whatever he saw, so I've been having a go myself.
About 30-40 minutes each
I'm finding this really fun. It feels really fresh. There are some pros and cons working like this. Dropping you in random places is obviously not always going to provide something interesting, but the cool thing is the composition is still entirely my own, being able to turn the camera full 360 gives me full control over the subject matter (within the scene obviously). And also, whilst the camera does have some hugely distorted perspective, it's quite fun to work with and makes the images quite dynamic. The pictures are usually super bad quality, but again I find this works as an advantage, especially as these are only quick studies.