You might have already tried this, but my sister has this great seal toy that lights up and makes noises when the baby kicks it. It's a great distraction. There is also another one in the range that comes with a little steering wheel that makes lights move on a picture panel.

Some babies do travel better when they get turned around to face the front. I'm not advocating you do this though! I kept DD facing backwards longer than most of our friends cause I wasn't willing to jeopardise her safety. Unfortunately you might just have to grin and bear it ,which is a lot easier said than done I know.