I have always liked the term "arse quiver".
It's that sinking feeling that you experience when you realise that you have over committed, been caught out or stuffed up, finally sinks home.
It is usually accompanied by a stuttering "but, but..." as you cling to some desperate excuse.
So I well and truly look forward to a butfull of quivering amongst the previous government's MPs as 7000 pages of their spending records are made public.
Of course being New Zealand, nothing of real consequence will happen as "mistakes and errors of judgement" are unearthed, but at least we will get to witness some fine examples of ring puckering.