The Xperia Mini features a 1200MaH battery, which is at the lower end of what we'd expect to find in a modern smartphone but understandable in a smaller unit.
Sony Ericsson itself rates the battery as good for 4.5 hours of talk time, or a ridiculously optimistic 340 hours of standby time according to the weird rules by which that's calculated. If you leave it in your sock drawer and never use it, that may be possible.
Obviously, the Xperia Mini has a smaller screen to power than most and that's reflected in the battery performance. We managed a good two days of light use from one charge, with the phone also easily surviving for a full day of pretty heavy web, Twitter and camera action.
You'll still need to be careful if you're planning on going too far away from the comforting hum of the national grid, but the Xperia Mini is unlikely to let you down. In standby mode, with GPS and Wi-Fi switched off, it barely registers any power drain at all over the course of a few hours.
Internally, the Xperia Mini supports sharing media via its Connected Devices DLNA app, which is a simple tool to turn the phone into a media server via Wi-Fi. This worked well, with the phone easily pairing with another DLNA mobile in a few seconds.
There's also an FM radio in here, which cleverly integrates with Sony Ericsson's TrackID system. If Zoe Ball turns the world on its head by playing a song you actually like, hitting the TrackID button records a sample and pings it off to a server for identification.
Plus, as with all modern Android phones on a decent version of the OS, the Xperia Mini can be turned into a portable wi-fi hotspot or used as a tethered USB modem - ideal for hooking a laptop into the 3G network.