When I was still in school I'd take it with me on the commute. There were a couple of spots near by my uni that were good for streetpasses so it was like an extra incentive. I have never really depleted that amount even years later... but sometimes I'll take my 3ds with me to work and it tops up again. I've never shaken it just to get play coins. To be honest, with my butter fingers I'm scared I'll toss it and smash it to bits lol.
