BIOM is one I owned for years. I had to sell it a month or two ago due to my financial disasters, but I managed it in AIM because of the volatility. The company has a promising product and every so often there's news that causes a spike in the price. It's declined or stayed the same since I had to sell it, but overall I was profitable in it because of playing it with AIM. You never know for sure with an upcoming product but I rather like the company.
Similarly for DNDN, which you also mentioned. I was in and out of that one. Very promising product and story in that one.