I posted some links to Burma campaign sites previously. Unfortunately it currently looks like the military is back in control there. I personally feel that disinvestment is a tool that should be used in support of the pro-democracy movement there, and this is the position of unions around the world including the FTUB.
However there are critics of this strategy, and it always worth at least listening to their arguments. Yesterday's Times ran this piece which is a well-argued opposing viewpoint. I don't agree with it, but it's worth a read. I'm not sure the bit about Premier Oil below is quite on the money from what I have heard from people closer to the action than me. I am pretty sure the allegations of forced labour were well substantiated.