Firoz and Ferhan Patel once "fired" themselves from their own company, drawing unemployment as they tried to make their dwindling resources last a little longer. In the end, AlertPay survived; it has about 5 million users in 197 countries. Still, that's a fraction of the size of PayPal, its major competitor, forcing the brothers to seek out niches. One promising potential new frontier: Partnering with cities in adapting parking meters to accept payment via smartphone. With contracts from Saskatoon, Saskatchewan, to West Palm Beach, Fla., AlertPay expects to generate an extra about $30 million in mobile payments over the next two years.