When the Vikings made their mead, did they take the time to fashion a nifty airlock? Did THEY sanitize their equipment!? NO, I SAY! They tipped over a bee's nest while raping and pillaging, and carried it home in a longboat alongside the plunder! Hell there might have been a touch of blood in the mix! After they figured out it got them drunk, they DRANK IT OUT OF THE SKULLS OF THE CONQUERED!
That's the flavor, NAY, the essence I want inside my mead. Any suggestions?
Actually they probably did use airlocks. I don't have a primary source, but see
http://www.nourishingtreasures.com/index.php/2012/05/15/the-science-behind-sauerkraut-fermentation/ under "What did traditional cultures use for ferments?" No, they didn't sanitize. From what I've read, a lot of traditional ferments were either wild fermentations, or a starter was used by fermenting in a clay jar that was never washed or by stirring with a special stick. These people didn't know anything about bacteria and attributed it all to spirits and such.
Heirloom starter cultures and wild fermentations are generally extremely hardy ecosystems of bacteria that can keep out competing species and adapt to small changes in environment. If you use less viable cultures like commercial yeast things may not be so robust, and a greater level of cleanliness may be needed.
My fermentation hero, Sandor Ellix Katz, likes to say in his books that traditional cultures used a lot of ingenuity to make fermentation work with the limited technology they had. Yes, you can spend hundreds on making beer, wine, or even sauerkraut by buying lots of products. Or, if you understand the concepts of what you're trying to make happen (and also what you're trying to prevent) you can experiment with different improvised solutions and see what you get. Think of all your creative ancestors and what they had to work with while you piece together your design!
For instance, if I had an interest in aging some mead without buying anything I might use a wine bottle. I'd take a rubber stopper and drill a hole in it, then press-fit and hot glue in place a piece of vinyl tubing that I lead to a small open jar filled with water next to the bottle. That's an airlock, and the only thing on that list I don't have sitting around is the stopper. Heck, you could probably even do it with an old cork.