You can do it with one of these :
http://www.maplin.co.uk/Search.aspx?...L26AJ&DOY=11m6
I bought one the other week, and it works fine - also lets you run sound through as well with the adapter
Thing to bear in mind though, you need a scart socket that will accept s-video, I had to use the third scart socket on my tv before I got a signal.
Set up the tv as an additional monitor on the laptop, drop the refresh rate down, and you should be away (you'll probably need to drop the screen size down as well)