A smokeless ashtray is a relatively simple device. It's just an ordinary ashtray with a battery powered fan inside the lid that pulls smoke through a tiny air filter to eliminate most of the odour. The type of smokeless ashtray you would buy at the store is encased in plastic and looks nice, but you can make a simple smokeless ashtray out of an ordinary ashtray and a few other supplies to save money.
Cut a hole in the bottom of a cardboard box the same circumference as your fan.
Turn the box on its side and align the back of the fan with the hole.
Tape a dryer sheet over the hole to act as an air filter.
Place the ashtray inside the box. As your cigarette rests in the ashtray, the fan will pull the smoke through the dryer sheet and filter the odour. Blow your smoke into the box to filter the smoke that you exhale.