Unclogging a drain lacking store bought products.? I've heard here are ways to unclog a drain without using chemicals...

I've heard here are ways to unclog a drain without using chemicals such as Drain-O, any suggestions?
Answers:    Most successful non-chemical drain cleaner is compressed air, they trade a Drain Blaster under 30 dollars, also can air at the home store, but the drain blaster will final a long time.
try pouring boiling hot water within it then hitting it near a toilet plunger