Here it is! This is a seat I bought from Canadian Tire for $14.99 (Ok, it was on sale, but the regular price is only $24.99.), and a milk crate I had around the house ;-) It's a fishing boat seat, and comes with a swivel on the base, which you won't need, so, when you're finished, you'll have a ball bearing swivel with as much as a 300 pound capacity (Visualize the last fisherman you saw sitting in a small aluminum boat.) that you can slip under a TV, or something.

Here's a front view. I screwed the seat to the middle of a square piece of chipboard I had lying around. It turns out to be quite important that the board is larger than the milk crate cross section. Just trust me on this.

Notice the piece of 1"x1" under the front edge between the chipboard, and the milk crate. This is how you adjust the tilt. You move that piece back and forth until the desired angle is reached.

I should note that this seems to be a slightly non-standard milk crate. It's a little larger in all directions than a standard crate, but a standard should still work. You may have to use a thicker piece of board to acheive a workable height, I suppose.

Ok, it's a bad photo. One day I may redo it. Notice the four screws behind the grid of the milk crate holding the seat to the chipboard. They are not the four screws that originally held the swivel to the seat. Those were too short to go through the chipboard, so don't forget to buy four screws, and four washers when you buy the seat. The two screws with large washers near the top of the photo are holding the milk crate to the chipboard. These screws are fairly long, and are not tight. This lets you tilt the front to get a reclining angle.

Here's what the swivel looks like. It's about eight inches square, and it must have a capacity approaching 300 pounds.