Creating An Identity Column In A View

I need a view that will:
1) select the distinct values in a column (the easy part)
2) assign the equivalent of an identity column to each row containing the distinct value it returns.

For example TableA contains 25 records but one of the columns only contains three unique values (say, 'A','B', & 'C').

This is what I want my view to return:

1 A
2 B
3 C

In other words, I need the view to assign the 1, 2 and 3 to the individual rows.

Thanks in advance for any pointers on this one.