is it possible to find a point on google maps using OS reference coordinates?

No, but although it's not as slick as Google Maps, http://www.streetmap.co.uk will accept OS grid refs.

Edit: This link will let you enter a gridref: http://maps.google.co.uk/maps/mpl?moduleurl=http://www.nearby.org.uk/google/gridref_mapplet.xml

Needs to be full 2-letter + 8-digit reference and for some reason it only centres the map, doesn't actually put a marker on.

[Edited on 29/5/09 by matt_claydon]

^^^ waht he said

and streetmap.co.uk has both the landranger and explorer OS maps built into it

There is a website somewhere that someone has written that has two windows.. the left one is google earth, the right is OS maps...

It does exactly what you want... but I cant remeber whos site it was on

i've got a feeling google earth can...