$100 a month

I live alone, and have $100 a month to save. I put $20 aside for emergencies, and $30 for gas. I live within walking distance of my job, but I like to travel for work on the weekends, so I spend that $30 a month on gas and various job things. So what should I do with this $50 a month? That's like the only money I can save, so I want to make the most of it. Should I save it? Invest it? What would be the best option?<br><br>I know it's a pretty small amount, but I'm a single guy living alone and I can barely make ends meet. I know it's no excuse, and I need to do something, but I'm in a very tough spot in life and I'm trying to do my best with what I have. <br>Any advice would be appreciated. TIA