We just picked up a Bionaire Ultra Slim Tower Fan Combo from our local Costco.  ($49.99)  The combo contains two fans.  One is a very slim tower fan that is 40 inches tall.  The 40-inch tower fan stows perfectly behind the right shoulder of the passenger between the seat and the Euro Chair in our 2350.  We wrapped a towel around it for travel and it appears to be perfectly secure in that spot, but we have yet to use it on a trip.
The fan puts out great air, has 3 speeds, a remote, and seems fairly quiet to us.  I'm planning on using it in combination with the Fantastic Fan in our ceiling.  We've tried using a smaller fan, and the a/c fan, but we weren't satisfied those.  We will be travelling in some hot weather in the next few weeks and I'm optimistic this will greatly aid in cooling.  I should add that the Bionaire combo doesn't get a lot of love on Amazon, but the reviews on Costco are better - we'll see!