By Bad Seed
This is a demo of the Ice Cream Sandwich alpha ROM for Xperia phones. It is available for download at Sony Ericsson Developer World. This ROM is strictly targeting advanced developers, and it will not work for ordinary everyday usage, as it only has a limited set of features working (the modem, Wi-Fi, Bluetooth, FM-radio and ANT+ is turned off, and GMS apps are not included as these features are not certified yet).
Please see http://developer.sonyericsson.com/wp/?p=4706 for more information.