This is so going to get flamed as too bike radar.
Interesting (or perhaps not for this forum) that everyone has gone with a choice of side. My initial though, you don't go along side you join the back of the queue.
I will only ever pass vehicles on their left hand side if I am in a seperate lane, or if they are stationary and have positioned themselves such that that I can't pass on the right AND most importantly there is a space for me to get to. I never want to be along side another moving vehicle unless we are in seperate lanes or a clear completable overtaking manouvre it taking place.
As for the legality of passing on the left, I don't think there is anything to say it is fine for any mode of transport. The section of the highway code on undertaking says it's acceptable in queues of slow moving traffic only, I don't recall any exemption for bicycles. Annoyingly there is a comment somewhere else in the highway code which says something like make sure to check your left hand mirror for bicycles that may be passing on the left. This seems to totally grey the area and I would prefer a blanket It's bad and wrong punnishable by death to pass on the left.
Oh yeah also another legality thought. In this situation, either side, you are trying to be alongside another vehicle within a single lane. Unless you can demonstrate that you had the lane and the vehicle came from behind to along side you then I think favour will fall to the vehicle and you'd be classed as in the wrong.
My actions turning right, if it's against heavy oncoming traffic I will sometimes go with the vehicle ahead of me, turning alongside their right into the oncoming lane of the road i'm turning into, if it is clear, so as to avoid sitting for a long time waiting for the next break in traffic.
Being a minute late for work isn't life threatening, making stupid i'm in a rush road manouvres coould be.