It's easy to talk about obvious stuff - ID cards for most, Trident for many (though if you look into it, the savings in both cases are tiny). Easy to say you would cut quangos, middle management, five-a-day coordinators, and waste. Much harder to come up with the difficult cuts.
Here is my list of painful cuts.
I would hold freeze public sector pay for this year, and hold it down to a 1 or 2 % increase the year after. The private sector has taken the hit so far; the public sector needs to share the pain. This is a big cut.
I would also stop all new public final salary pension schemes, and limit public pensions to about £40000 a year (with top ups available via defined contributions if desired).
I would cut the police force by about 10% over the next 5 years - through natural churn as much as possible. Police numbers aren't the bottleneck any more - it is much more police time.
I would cut all new roadbuilding programmes. I would allow private companies to finance new roads, with the rights to charge tolls on them for 40 years.
I would make much of SureStart means tested. Everyone should be able to continue full access, but there should be more co-payment, like with prescription charges at the moment.
I would scrap the child trust fund, and means test tax credits.
I would cut the school and hospital capital budgets by about 25%. Most of the buildings are in good condition.
The really depressing thing is that all the stuff I've mentioned would only go a miniscule way towards filling the annual deficit.
We're in for a really crap few years.