1. Calcio Storico Fiorentiohttp://5thin.gs/Kjexz3

A revived Italian football/rugby variant played annually in the center of Florence, Italy each June. It is noted for its violence and seemingly mob-tactics. Great for operatic soundtracks on YouTube videos.

2. Extreme Baseball http://5thin.gs/Kjg1ctTwo pitchers, two mounds, two homeplates, two sets of fielders, and one team runs clockwise around the bases, Extreme Baseball is perhaps not gonna be around for long. Its professional league seems to be up for sale.

3. Kronumhttp://5thin.gs/Kjh3Fr

An interesting mix of soccer, basketball and perhaps Gaelic football, all played on a 4-goal, circle field. 

4. Sepak Takrawhttp://5thin.gs/JdeDqD

A traditional Thai sport played all over Southeast Asia, Sepak Takraw is a soccer/badminton combination, and it acrobatics are astounding.

5. Bandyhttp://5thin.gs/Jdfs2H

"Winter football" is one name for this game that is essentially hockey players playing association football on an ice field with a small ball and sticks.