Tories. I'm in full agreement with Matthew here; I really suspect that the mood music about "austerity" (plays well with the demographics) and "IMF" is actually preparing the ground for the Conservatives to pull a deliberate financial freakout once in office. Osborne has been pushing a line that We Have No Idea How Bad It Really Is for some time.
One of the main uses of this institution is as a combined reason and excuse to push through horrible right-wing bollocks that you'd never get away with in normal politics, and the total collapse of its influence in the 2000s seems to have had remarkably little effect on it. They are still ordering countries like Iceland and Hungary to put up interest rates in order to pull in hot money, something which just isn't ever going to happen now and is only explicable in economic terms by a desire to push down wages. It is also explicable in anthropological terms as a cargo cult - do the same things in exactly the same way and maybe we'll be important like we were in the 80s!
My guesses for the targets are three well-known TLAs - the NHS, the BBC, and the MOD, especially those bits of it that represent independent enabling capabilities with regard to the US. After all, we can do nothing; the IMF made us do it. There is an alternative view that Gideon will be given the boot by a Ken Clarke-led wave of realism, but then, a lot of people have been made fools of hoping for the Tories to listen to Ken Clarke.
How can we resist this? IMF riots may be traditional, but they have the fault that they usually happen after Jeffrey Sachs is called in and the damage is done. After all, as "RickDFL" points out in comments at the Washington Monthly, the lack of universal healthcare in the US is a major structural advantage for the Right.