OwnCloud is a free (libre), open source equivalent to DropBox. As well as the program you install on your server, it has free desktop sync clients for Linux, Windows and Mac, and apps for Android and iOS. I’m just going to cover the server side of things for your Pi in this tutorial, because the desktop client can be found in the Ubuntu repos, and the app is on the Play Store. If you want the Android app free of charge, then install it via F-Droid.
If you’ve read some of the other articles on the site, you may have gathered that I have three RasPis doing useful things around my home:
All three of these ran reasonably quickly out of the box, but because the Pi is such a low powered device, every little performance boost helps. Having said that, this is no small improvement, and the performance gain is instantly apparent.
Get_iplayer is a FOSS program that allows you to download TV and radio from BBC iPlayer. The original developer stopped maintaining it at one point, but since it was licensed using the GPLv3 a few others were able to take over, and it’s still actively maintained. Hooray for free software! 
You may find it useful if you have a slow internet connection at home that causes iPlayer to stutter, or if you want to download a TV show and watch it later when you’re not connected to the internet (e.g. on a tablet during a long plane journey).