What do a seven-millimeter-thick portable speaker, a blood-sampling catheter designed to mimic a mosquito’s proboscis, and habanero-pineapple hot sauce have in common? They’re all destined for the Darden School of Business, three of more than two dozen business ideas from a group of entrepreneurs who will form the first class to go through UVA’s new W.L. Lyons Brown III Innovation Laboratory Incubator.