Have store front, need business ideas

I have a small store front that i used as an office for my carpet cleaning business. I have since started running that business out of my house because I have become to busy and my wife does the books from our home office. I still have this space that is in a strip center. It's small, 10'x15' but is very nice and i have storage/warehouse space in the back. I am looking for a small business to put in that location. A good friend of mine is wanting to invest with me in some sort of business since I have that space sitting doing nothing. I thought maybe a gold buying shop or selling knives. Just looking to bring in some extra income and help my buddy stay busy. We are both very passionate when it comes to succeeding. I started my carpet cleaning company last year and it took of tremendously. hard work and marketing are to thank for that. Anyways, any ideas for a business that could be ran out of a space this small would be appreciated.