Most "bug lights" attract bugs using a flourescent light; they're more efficient than incandescents, but big bug zappers use as much as 80watts of power -- for just the light!
I propose using LEDs to attract bugs to a bug zapper. Since they're about 10x more efficient than flourescents, one should
be able to make a moderately sized zapper, which uses so little energy for it's lights that it could be powered by solar cells (during the day) and rechargable batteries (during the night -- the batteries would of course be charged by the solar cells).
The bug zapping part also consumes relatively few watts, so all that's needed is an appropriately large capacitor.
Done right, the capacitor could be stopped from discharging any more energy on any one zap than is needed to kill one bug -- this would keep it from discharging completely, and it would take much less time and energy to recharge. Not to mention, it could possibly zap multiple bugs starting from a single (large) charge.