http://www.pro-oiler.com
The pro-oiler (in contrast to the scottoiler) lubricates and cleans the chain without the "drip rate" being changed because of temperature induced viscosity changes (which can be huge with a scottoiler). It also compensates for speed because of the sensor or linkage to the digital speedometer, so no leaks at standstill and so efficient it uses about 5 times less oil (any motoroil, no special scottoil) so you can use a tiny reservoir. And the engine vacuum isn't affected since it's all electronic.