For $319, you can turn you AR into a simulated full-auto with a bump-fire stock that fits over the buffer tube. There are no moving parts in the stock itself and it has been approved by the BATFE. However, I wonder how long it will take for the ATF to reverese their approval. The Firearm Blog reported on this item:

http://www.thefirearmblog.com/blog/2...ock-for-ar-15/

Slide Fire Solutions:
http://slidefiresolutions.com/Product-SSAR-15.html

Slide Fire Solutions, Inc. introduces the patent pending Slide Stock for the AR-15 (SSAR-15).

Utilizing the SSAR-15's revolutionary "Slide Stock" technology and ergonomic design - individuals are now able to greatly reduce or eliminate the negative effect of recoil.

In addition, amputees and other individuals that are unable to manipulate the trigger using the traditional method will now have additional options using the SSAR-15.

The enabled sportsman, with the addition of a stationary link, can now discharge the firearm utilizing other techniques. For instance, an Army veteran that lost their hand in Iraqi to an IED can now use the SSAR-15 and apply forward muscular pressure to a vertical forward grip modified to work with their prosthetics to fire their rifle.