Is there difficulty implementing constant-time algorithms for async processors? For example, it is very desirable that every crypto operation takes exactly the same amount of time, to avoid timing attacks.
Here's another cool thing: by using a dual-rail encoding (one wire being high means a bit is 0, the other wire being high means the bit is 1) you can design logic that consumes roughly constant power no matter what the operands are. This makes power-analysis attacks a lot more difficult.
Here's a paper on all this that you may enjoy:
http://www.gemplus.com/smart/rd/publications/pdf/MAM03as.pdf
Unfortunately, to match the minimum to the maximum, you would likely have to design your implementation to be very slow. In the constant time case you remove all the pipelining advantages, as you would be required to 'fill' the pipeline.