Gnome clickomania, or glickomania, is a simple, but dangerously
addictive puzzle. The objective is to clear the board of all tiles
by removing groups of identical adjacent tiles. Tiles fall downwards
to fill empty gaps, and from right to left to fill empty columns.
A slight variation of clickomania is known as "the same game" and
it has been implemented in KDE (ksame), Gnome (gsame), and most
handhelds. The most significant difference is in the scoring: in
clickomania the goal is to clear the board, whereas in "same" the
objective is to remove as large groups as possible.

Glickomania can be very challenging, but this implementation is
designed to be relaxing: there is no clock and the user has unlimited
undo and redo. Contrary to all other implementations I know of,
glickomania ensures all problems presented to the player are indeed
solvable.