Reaper Miniatures Bones Kickstarter is being shipped out to backers, there are a lot of people that are going to be painting and basing their new miniatures.
I've been hearing that some folks are finding that the minis are so much lighter than they are used to and they are having problems due to the lightweight nature when they are painting or using these figures.
One quick and simple tip is to glue an appropriate sized fender washer to the bottom of your mini base. Bought in bulk, a box of 100 1" fender washers goes for $6-$10. They add a good amount of weight and can be used with magnets. Make sure you get a Fender washer, which has a lot more metal that a regular washer.