Did you see me by any chance? I was the youngest of the 200+ people
I set off by VIP bus from Mo Chit at 8:30pm on sunday. My bus was bound for Nong Khai and came to a pricey 715 baht.
From the side of the road I took a tuk tuk who ignored my request to go to the border and dropped me off at a dodgy visa travel agency. He didnt get paid for his trouble. Too knackered to argue I paid 2000 baht at the travel agency. That got me 36 usd, the forms for the visa, a lift to the border, a lift from the border to the embassy in Vientiane and a Lift from the embassy to downtown Vientiane by the river.
I followed the advice of a German guy I met at the embassy and stayed at a reasonable hotel by the river. The hotel room had a shower with hot water, cable tv, a fridge and air con - not bad for 10 usd.
The visa process itself was exactly like everyone else before me has said - painfree

They did seem to have a crazy system at the embassy though. queue for ages and submit your passport and forms outside. Them queue for ages again inside and pay.
On my way to collect my passport from the embassy yesterday, I met a friendly Laos bloke and he gave me a lift in the back of his pick up to the embassy. Ha take that tuk tuk drivers!
After collecting my passport I ignored the long line of tuk tuks and walked to the bus station. 80b bought a bus ticket from Vientiane to Udon. That seemed like quite a bargain
From Udon I paid 440 baht for a "vip" bus to Bangkok. Vip turned out to mean air conditioned with no leg room

I left Udon at 8pm and after a loooong journey with very little sleep made it back to Mo Chit at 5:30am. Next time I will take the train - lesson learned.