|Subject: Re: Travel between Washington and New York|
Fortunately the DC/NY corridor is heavily travelled so you have more and cheaper (by US standards, anyway) options than for other routes. The train will be about USD $70 one way and will take about 3.5 hrs, avg. A bus would be about $50 one way and will take about 4.5 hrs. Plane fare can vary a lot, but I doubt you'd find anything cheaper than the bus one-way. If you're travelling round-trip, you may be able to find a plane fare that's more economical.
Both Amtrak and Greyhound often have sales and promotions that might get you a lower fare.
If it were me, and I were travelling one-way, I'd spend a bit more and take the train.
Hope this helps,
Cindy in Harrisonburg, VA