I dont know whether this is applicable to this post but from my understanding Hahnel have released a combi TF and trigger system [ see www.hahnel.ie ] which enables the possibility for off camera flash or at least I think it does? It uses a combination of trigger and recievers to enable this set up and they have a system for all sony DSLR's.
Perhaps someone could check this out to see if I have got the correct details. Cheers, malcy

Yes it looks like they have a transmitter that fits Sony cameras directly. But there are a few compnaies that do and these look like some of the ones you can get from e-bay.

http://smdv.en.ec21.com/Flash_Triggers- ... 52919.html

these are about the best made i've seen so far