I have now managed to build ubuntu-touch for all Sony Xperia devices except zeus and zeusc.

The generic ubuntu part here: http://cdimage.ubuntu.com/ubuntu-tou...blet-armhf.zip
Device-specific parts:

anzu: http://adf.ly/NcOzr
coconut: http://adf.ly/NcP7W
haida: http://adf.ly/NcPB4
hallon: http://adf.ly/NcPF2
iyokan: http://adf.ly/NcPKM
mango: http://adf.ly/NcPOI
satsuma: http://adf.ly/NcPS7
smultron: http://adf.ly/NcPVe
urushi: http://adf.ly/NcPcC

To fix the resolution for hdpi: http://adf.ly/NcPgk Thanks jasousa!
To fix the resolution for mdpi: https://www.dropbox.com/s/srbwyv7pnr...y_Kakalko4.zip Thanks kakalko4!

Detailed instructions:
First download the 2 zip-files above and the resolution fix for your device.
If you don't have unlocked your bootloader yet, go to http://unlockbootloader.sonymobile.com and unlock it while you are waiting for the downloads to finish. (This will make a factory reset, so make a backup of your data)
The generic ubuntu-part is installed onto a second partition on the SD-Card (ext4), that you have to create first. You can do this with a linux computer, butmake a backup of your data first. The partition has to be at least 2GB, better more.
If you don't have linux, you can download another kernel for your device, which contains a non modified version of CWM and flash it with "fasboot flash boot /path/to/boot.img. Then under advanced -> partition sd-card you can create a new ext4 partition, but use 2048M or 4096M, because ubuntu takes a lot of space when unpacking. !WARNING!, using this method deletes all data you have on your sd-card, make a backup first.
unpack the boot.img from your downloaded zip containing the device-specific part.
then flash it using fastboot: type in terminal "sudo fastboot flash boot /path/to/extracted/boot.img"
copy the downloaded zips onto sd-card (1. partition / fat)
boot your phone into CWM by pressing the volume-down button continuously while booting
flash the downloaded zip with the device-specific part onto your device first, then ubuntu part and at last the appropriate fix for the resolution
reboot into system and try it out (at first you will see a black screen for a minute or two, but then ubuntu should start)

Of course any developers are welcome, that want to help fixing the current bugs like enabling the new daily images of ubuntu-touch which currently only produce a black screen (officiallysonyrebel is working on it) or make dual-boot available.

Source changes will be uploaded to http://adf.ly/NcQ0a

Some of you requested screenshots, but I give you a Video:
Thanks kakalko4!