TkTable - a table (spreadsheet) Widget for Tk
TkTable is a full-featured 2D table widget for Tk. It supports images, embedded windows, varying colors and fonts, and more.
For another example check the 'tk table calendar'
The tktable.py file, a python wrapper for the Tcl/Tk TkTable widget, is in the demo directory of the source code for TkTable, available at http://tktable.sf.net. As it says in its headers, it is an example implementation only. I believe there are other tkTable Python modules available. The file tktable.py file can be run to test the TkTable installation.
Update: A complete TkTable wrapper can be found at http://tkinter.unpy.net/wiki/TkTableWrapper now.