Snap mesh to drawn line

After making a few detailed models, I started wondering if there was a tool that allows you to select some vertices or an edge loop and draw a line, and have the selected vertices snap to the closest point on the line (within the plane of the screen like the 3d cursor). This would save a lot of time pushing individual verts around and be really handy for people with graphics tablets.

Does this exist or should I make a feature request? :confused: