Uniquely identify raster cell in which point falls

[LornaMurison]

Hello,
I am trying to delineate catchments based on a flow direction grid.  Some of the points I am using to delineate catchments fall on the same grid cell.  I am looking for a way to identify these points.  Is there a way to attribute each point with a unique identifier representing the grid cell it falls on?  Or is there a way to convert the raster to a polygon where each cell is a separate feature?
Thank-you.

[LornaMurison]

This thread is exactly what I am looking for:
http://forums.esri.com/Thread.asp?c=93&f=995&t=271861
However, the forumula: * 9 + ($$RowMap Mod 3) * 3 + ($$ColMap Mod 3) is giving me a syntax error around ).

Any help is appreciated

[LornaMurison]

Hi Bill,
I separated out the expressions and the error occurs when I try to add Mod 3.

I have, however, found a more appropriate solution to the original problem by taking the points I am interested in, converted those to raster, and then back to polygon.  This way I can give them each unique IDs and I am only dealing with 7000 or so cells.

Thank you for your help.