Portland reader, Doug M. submits this cheap weight tip:
Aluminum/steel steerer tubes: Use a compression plug instead of setting a star nut. Follow instructions above.
Sorry I have no pictures, but I have no camera, nor a gram scale.
I have seen people replace their topcap with simple things like beer bottle caps, or you can do as I did and fabricate a carbon top cap (like the photo above).
Some people will say that a stem will crush your carbon steerer tube, check with the manufacturer before you do this one. I've never had a problem with it. But your results may vary. I was able to save about 14 grams if you're using a starnut and more if you are using a compression plug.
If you have a cheap weight dropping tip email it to me at plusonelap at gmail dot com.