Budget Watch Collecting/Quicky lube
Disclaimer: While this method is reasonably likely to get a mechanical watch running again, it is also likely to cause greatly increased wear if the watch is run much afterwards. I recommend this in limited circumstances only. One is to sort watches--If you can get a watch running with this, a standard clean/lube/regulate will very likely put the watch in good condition. The other situation is when a watch would be interesting, but even in good running condition would not be worth the cost of a servicing.
With that in mind--Many watches can be resurrected by oiling the critical friction surfaces that are accessible without disassembly. If you can get an oiler to the escape wheel, a drop of oil on each of about 3 teeth will be the most likely to revive the watch. Be extremely careful--you will be working in the area of the most fragile parts of the watch. Additionally, oil to each of the visible pivot jewels can help.