In the networking world Fulcrum built some very low latency switch chips used in switch routers using asynchronous logic. The Alta switch chip was the last of that generation.

http://www.hotchips.org/wp-content/uploads/hc_archives/hc23/...

Intel acquired Fulcrum and has not had a new product. One can speculate that they were acquired in part for their experience and tool to design asynchronous pipelines.

In the DSP world Octasic makes DSPs that use asynchronous desisns:

http://www.octasic.com/technology/opus-dsp-architecture