Or, the other direction! If all properties remain the same, consider the idea of glass. Under the right circumstances, glass can be exceptionally strong - perhaps ultradense glass would retain its clarity, while gaining tremendous strength. It'd be tremendous fun to experiment, here.

I'm also curious about miniaturisation going the other direction - not necessarily of parts, but of data. Microfilm could perhaps be reduced another level of size, and weight change wouldn't necessarily be an...

...oh my. Oh my. Lenses and mirrors. Made to current precision capabilities large, then reduced - making currently-impossibly-precise equipment! Or made to best current precision capabilities at largest size currently workable, then enlarged - a little less precise, perhaps, but the light-gathering capabilities would be magnificent, and the weight would be so much less of an issue!

Not to mention transistors and vacuum tubes. Transistor radios the size of a business card, perhaps? And computers - as they continue to grow, something like this might well solve many problems. And they might even be even faster, as the electrons would have less wire to travel. I should ask some of the engineering fellows, I'm sure they'd have thoughts on this.