Carry AAA "Premier" card. One of three free tows is good up to 200 miles. Another two free tows, up to 100 miles. I carry it with me all the times. If I get a flat, no big deal, I call AAA and they'll come and take my car to the tire shop. Also, I can get a free rental car (only 1 day) provided by AAA.
Carrying an AAA card weighs only few grams, rather than carrying 65 pound spare tire in the trunk and it uses up the space.
2007 BMW 335i Sedan, Montego Blue with Lemon seats, AluFelgen CS7 rims & Continental DW tires