Hitching in Laos is very much divided to north and south part of the country. While in south it is relatively easy to hitchike for 300 KM a day, in the north it's hard to go more then 150 a day. it can get pretty hard, and that was also Worldhitch's experience. It can take a long time to be picked up, as just a few cars drive on the so called 'highway'. the highway is a dirt road, paved randomly, one lane each. Looking at the amount of cars (in January 2011 and 2012) there are around 1 (pick up, car, truck) per 6 minutes. Very different then hitching in Thailand. But even in the north it is still possible to get a lift. Solo HH can get a ride between villages with one of the many bikes that stroll all over the country Near the border with Vietnam, the road 7 are many logging trucks, coming from China. They speak no English most of the time. Try the pickup trucks and point that you want to sit in the back. It helps to say in advance that you have no money and it can also be a good idea to have a local person write down a few sentences like "have no money", "short distance is ok" etc. There are more then a few improvised pickups that will give you a ride for less money then the organized busses. sometimes it seems cheaper to go with these pickups Because from the 10 hitches, you need to pay 3 of them. [rule of thumb: 30-40.000 kip per 100 km for a real hitch, or 10.000 per person (per 30km) for a bus-truck.
Still, if you are determined to hitchhike for free through Laos, it can be done, even in the north (the south is very easy, similar to Thailand). Since almost nobody can speak English, and they will expect a payment for the rides, it is essential that you get yourself to be understood: a hitchhiking letter may help you a lot with that, and will also help you to get helped by the locals in order to find free rides to your destination. Aside from that, be prepared for the long waits, have lots of patience and to it mostly for the fun!
In the 80's a lot of people went to Russia for their studies, and these are often people who cars these days, so you might be able to use your Russian skills.
You should be aware that some maps of Laos (Google Maps in particular is one) are not accurate.
It is illegal to sleep outside in Laos. If you are caught, you will be fined. [source required]