I'm sure when the charities first came up with the guerrilla-style 'pavement ambush' tactic it generated some fantastic results.

But it didn't take long for people to get wise and all of a sudden those over-friendly volunteers became just the latest 'avoid at all costs' obstacle on London's streets.

Of course, this doesn't mean we don't like charities any more - we've still got indents from wearing our red noses, and you wouldn't believe how much of Bono's RED stuff we've managed to accumulate, even with its debatable impact - it just means that we have to look harder for one that won't bumrush you with a clipboard everytime you step outside.

For instance, we've been fans of Timebank for quite a while now. The idea is you donate chunks of time every month which has the added bonus of making you get off your arse and do something more than just set up a direct debit. Or just look at the huge amount of projects the Imperial College is involved with.