It is not really design per se, but if there was an interesting project, I'd tell my boss that I was working on that.
Best move I ever made, I learned enough that the knowledge pretty locked down the next job.
Downside? I had to do nuclear spectroscopy in an unheated concrete building in the winter. No amount of Carhart overalls will keep you warm, and PC's running Windows 3.1 just don't put out that much heat.
Upside? Besides the future job, it resulted in my only published, refereed journal paper, and got me a trip to present it someplace slightly (warmer San Fransisco in October).
I still have the poster :-)