If you've ever made a presentation (or shown a friend that hilarious YouTube clip you found) on your laptop, you've probably played the fun little game of trying to give the trackpad a nudge just often enough to keep the screen from dimming in the middle of it. You can edit your Energy Saver preferences before you start ... or you can use a new program called Jolt (no relation to the cola) to temporarily disable the Energy Saver settings.
Jolt places a small lightning bolt icon in your menubar. When you click it, it lights up to let you know you're safe from the mildly embarrassing mid-presentation screen dim. The full version of Jolt allows for variable timer settings ranging from 3 minutes to forever. The full version will set you back a whole $5, half of which is donated to charity (visit the Jolt page for a list of charities and a free trial).
Update: For clarification, only the full version of Jolt costs $5, Jolt Lite is available for free (but only offers one timer setting). Caffeine, which we've mentioned before, is also available for free.