Let me share you some of our ways.
When we were still in college we used to collect P5-coin in a container. 'Nung napapansin namin na masyado nang marami P5-coin sa sirkulasyon ng pera, we made it to P10-coin. 'Nung napapansin namin na wala nang natitira sa pera namin dahil napupunta na lahat sa savings we made it to P200-bill. Same case as the P5-coin and P10-coin, 'nung masyado nang maraming P200-bill sa sirkulasyon ng pera sa Pinas, we stopped. Hehe! If I remember it right, we reached P20,000 just collecting those coins and bills. Not bad, di ba? We used that money as additional pocket money 'nung nagpunta kami ng Singapore. Success! 
Just before we decided to stop collecting, we got a cheque from Google Adsense (the fruit of our hard work, naks!). In the Philippines, you can't just easily encash a dollar cheque. We tried it in Citibank, we tried it in BDO but we got no luck. A BDO staff just asked us to open a dollar account and there we will deposit our cheque. And so, we did. Success, may pera na kami! But instead of using it, we decided to maintain our dollar account and deposit some X dollar every month. Unluckily, the value of the US Dollar is going down. Sayang ang savings if we use it today. Luge pa. Pero umaasa pa rin kami na tataas ang value ng dollar bago namin magamit yung pera. And at least, may savings pa rin..
Lastly, we have our Adsense account. We put Google Ads in our blogs and websites and we earn few cents everyday. Few cents might be small but all the cents will all add up. We are not expecting alot from it anyway. Kung wala kaming $ for the day, ok lang pero kung meron, edi masaya! Success pa rin, at least nakapag-share kami.. 