First off, I barely know anything about DNA code, so I can't do any of this myself. However, many of these ideas can be accomplished by crude gene splicing (copy paste, with a few alterations).
1. Fractal defensive shield
After messing around with Fractals, and the other bots in that thread, I got one type of bot to put out what looked like a comet, curving outward and down. I then realize that this could be used as some sort of defense (given that the fractal was started with a very small percentage of the parent's energy) or simply a countermeasure to superior eyesight. For example, if the bot is hit, and puts its view to max and still detects no non-friendlies, put up the fractal shield in the direction of fire, and run like hell. Could also be used as an attack (if the bots energy is high enough for this to be acceptable) against a small number of enemy bots.
2. Biological tie attack missiles
My brother, De-Maskus, was messing with Alga Minimalis giving it two alterations that were first noticed in someones evosim that enabled the Alga to move using child bots as, literally, jet engines. Depending on the energy level of the bot (and HEAVILY depending on the friction settings) some of these 'nacelles' would shoot forward at high speed. They looked remarkably like missiles, and seemed to not require very much energy at all to fire. My idea was, coupled with some sort of long range spotting (may be available in a large MB or some sort of hive bot) these 'missiles' could be purposely created and fired at an organism, and when they get close, either tie attack or fire instakill shots, or a nasty virus. (Forced cancer, anyone?)
3. Fractal MultiBots
Ever since 'Fractals' was created, we've all wanted to see an effective multibot made from it. Combining it with some sort of movement routines, and hopefully some kind of defense or harvesting routines, may yield a crude yet interesting bot. If anyone who is experienced with DNA has the time, I would really appreciate it if someone could inject either Fractals or an existing MB with the code from either, we may have the workings of a neat MB. Combine these genes with swarming functions, and maybe write the code with PyBot or that other thing, we may have the neatest bot made in a while.