These work pretty good
Threaded Drywall Anchors
Known by the trade names such as "EZ-Ancor" or "Zip-It", this type of anchor is a basically a large, threaded nut with a point on the end! The large threads are intended to hold strongly into drywall and will accept #6 or #8 sheet metal screws.
To install these anchors, it is advisable to first use an awl to punch a small hole the size of the "point" in the drywall. Though they are designed to be "self-starting", providing this starter hole will give you a more accurate installation. Then screw the anchor into the drywall with a Philip's head screwdriver until the head is flat against the wall surface. These can also be installed with a screw gun or a regular power drill with a screwdriver attachment. The surface of the drywall may distort, tear or slightly "buckle" as the anchor is installed... this is perfectly normal and to be expected.