GlobalGiving.co.uk. It subverts the bog agency model of give us your aid charity and we’ll decide who gets it.
To quote from their press release:

GlobalGiving.co.uk is a website enabling individuals to give directly to hundreds of well-vetted grassroots charity projects in over 70 countries, mostly in the developing world. Donors can also tangibly see the impact of their donations on the communities concerned through regular progress updates from project leaders. Projects range from providing clean water to villages in Morocco, enabling Guatemalan women to set up small-scale businesses, or helping Nepalis produce pedal-generated light as an alternative to dirty kerosene lamps.
The GlobalGiving concept was established in 2001 in the US by two former World Bank executives, Dennis Whittle and Mari Kuraishi. Since then, GlobalGiving.com has generated over $12 million to fund over 1,000 grassroots development projects. GlobalGiving.co.uk now offers the same exciting types of project opportunities to UK based donors.
Charities have long grappled with the issue of giving supporters a sense of the impact of their donations, and avoiding the uncertain feeling that donors often experience after sending a cheque. Meanwhile, outstanding projects struggle to obtain financing throughout the developing world. With GlobalGiving.co.uk individual donors can choose how much they wish to give – as little as £5 – and to which causes. In fact, many project leaders insist that the steady amounts of small donations are the ones responsible for projects reaching their goals.

Similar but on some level more individual than justgiving. For more then just this truncated hello please see Beth, David Wilcox, Dennis Whittle, and their own blog here.