What is the cheapest way to get from Eindhoven or Eindhoven airport to Amsterdam and back?
I'm currently working in our Eindhoven office and can see the runway from here ;)
Hitchhiking is unlikely to work; there's no decent location to get picked up near the airport. The A2 highway is close, yes, but there's no parking lot or something similar. Furthermore, you're not allowed to walk on the highway itself. You'd have to post on the on-ramp, but there's no room to stop there.
The train would be easy, and there are 7 buses per hour to the station. Pick the 401 (22 minutes; it uses a reserved buslane so no traffic jams); the 103 takes a horrible detour. Costs 3 euros one way, and you'll need coins for that.
There are actually 4 trains per hour to Amsterdam; two of them go to Central Station and the other 2 go to Amsterdam Airport (south of the city). Depending on where you're going, either route is an option. All trains stop in Utrecht, where you can transfer.
The cheapest is probably hitch hiking. It's about 120km, and the A2 runs basically the whole way, but I've no idea how easy it would actually be to get picked up.
The easiest is probably taking the train. During the day, there are 2 trains an hour from Eindhoven direct to Amsterdam Central, journey time of 1:20. The ticket costs €17.50 for a single in 2nd class. Alternately, there are 4 trains an hour (2 direct, 2 changing in Utrecht) which will take you to Amsterdam's Schipol Airport, journey time of 1:27 (with or without the change), at a cost of €18.00 single in 2nd class. You can look up times and prices on ns.nl, which is the website of the Dutch Railways.
I was about to suggest the bus / shuttle service as well, but it looks like the locals already disagreed on this option :)
If your trip is still a few weeks away and the train or bus is no option, you might try your luck by placing a listing on one of the rideshare sites:
This question is pretty old but I came across it when trying to find some cheap way to travel from Eindhoven to Amsterdam.
If anyone would like to save some money I recommend group train tickets - the price drops from 20 to 7 euros per person and the great thing is that the group doesn't have to travel together, not even the same train, only the destination needs to be the same. More info in this thread: Group travel in the train in the Netherlands, how does it work?.
Hitchhiking is by far the cheapest option. I have had personal experience hitching across Holland both in and out of Eindhoven and I've never wited much longer than 1 hour maximum for a lift pretty much anywhere in Holland.
When hitching my best advice is to always hitch from a petrol station, as that way you can talk to drivers to;
A: determine if they're going the same way as you
B: critically assess risk and not just take the first thing that comes along.
I believe the petrol station method is such an advantage it's worth either asking someone at the airport (also good hitching locations often) for a lift to the 1st service station on your way or even catch a taxi there.
When flying in, the bus they supply is only slightly more expensive than train tickets to Amsterdam, slightly less expensive than paying for the bus to the station and the train without a public transport chip card.
The time it is taking is also a bit less than taking the bus to the station and the train from there.
Better option next time is to fly to Amsterdam airport rather than to Eindhoven, as it is much cheaper and faster and not having to pay for the bus or train will make up for the difference in flight prices.
This comparison in prices held true over the last couple of years, I do not expect it to change by much as Ryan air seems to dictate that price level.