Which fun timing methods are there?

Hourglass

A player's thinking time is gradually reduced while, at the same time, his opponent's is increased. This is an exciting alternative to the traditional "quickie" game.

Gong

Before double-timer clocks were introduced, tournaments were often controlled with a gong. The gong was used to mark a fixed time for each move. The DGT Clock's Gong method gives a fixed time of ten seconds for the left-hand player, then for the right-hand player; then it repeats this pattern.