a good mattress topper that is not to warm?

Use a Goose Down Comforter. It allows you to breath so you don't get too hot. Lol, that didn't come out the way I wanted it too. I should say, down doesn't clump up and end up compacted. It allows air to pass through preventing your body heat from rising too high while you sleep. Does that sound better? The way I said it the first time makes me wonder if other comforters would stop you from breathing all together! I feel so goofy sometimes.

Use memory foam or just a blanket :)