Bigbad
You may not believe this, but my autocorrect changed your name, it wasn't me. Apologies if you thought I was being offensive.
As mentioned before, foreign aid and investment (the two are linked) benefits Britain in the long term, because it gives us a presence in emerging economies. We don't do it purely out of altruism.
I think we need to focus on the big spend items to reduce the burden on taxpayers.
For a start - abolish the state pension (which is by far the biggest drain on the public purse) and instead encourage everyone to pay into private pension schemes.
There could be tax incentives to help the transition.
And get rid of all child benefits. If people cannot afford to have kids, they should wait until their salaries are large enough.
And introduce a system whereby all recipients of treatment on the NHS have to prove that they are paying NI contributions. Perhaps a card proving NI submissions could be produced, which would immediately kill off the 'health tourism' issue.
Oh, and get international companies who trade in the UK to pay corporation tax at a fair level, and not the same amount of tax that a Mcdonalds manager pays.
If you implement all these strategies, I'm sure that we would have far more money to play with, than the 0.7% of GDP that the cessation of foreign aid would provide.