Edge slide for vertices

Could someone make the edge slide tool works for a single vertex?
I think that it’s not so hard to make. The mouse wheel change the edge in which the vertex moves, and the mouse movement moves the vertex.
http://img641.imageshack.us/img641/1964/vertslide.jpg
Thanks for attention!

Sorry! However it don’t works with the edge slide command, which is my idea. I hope it will be implemented in the new version.
Saluti!

i dont think its possible to slide a vertex on the edge

there is in 2.5 a command to slide a vertex along and edge
is that what you want ?
happy 2.5

You can achieve same result with custom transform orientation.

Choose and select the edge.
Create transform orientation. (Ctrl Alt Space)
Select vertex.
Grab/Move vertex on Z axis of Edge orientation. G,Z,Z

or
Choose and select the edge.
Align View to Selected. Shift Numpad 1.
Select vertex.
Grab/Move vertex on Y axis of View orientation.

Or:

Set the Pivot Point to Active Element (Alt+.)
Select Vertex A (the vertex you want to slide)
Then shift-select Vertex B (the vertex you want to slide towards) and scale