My brother just had an electrician install an exterior flood light fixture and outlet for his patio. Apparently it needed a permit, he lives next to the vice-mayor, and not many electricians can pull a permit in our little suburb. He wanted a timer on the circuit, that will actually be used rarely, and he likes to use compact flourescent flood bulbs.
The electrician installed a decent quality electronic timer in a box alongside a duplex switch where the top switch is a two-way and the bottom is a three way. The timer is wired for a three-way switch against the three-way switch next to it. Both the three-way switch and the timer then feed the two-way switch. The three-way switch then acts as a bypass for the timer in the circuit, and the two-way switch controls the light on and off even with the timer on.
I should note that in testing, the bulbs run on the timer with no flicker. However, it is well known that CF bulbs with electronic ballasts and electronic timers mess with each other. The box the timer came in did not mention anything about CF or electronic ballast compatibility.
Now, I have to ask, why such an elaborate setup? The only thing I can think of is that the 3-way bypass will prevent the CF bulbs and timer from messing up each other except when the timer is actually used. Still, why not just get a timer rated for CF bulbs with a manual bypass switch?