I always try and use one of my several reusable water bottles whenever possible, but sometimes I forget, or somehow they've all ended up in the dirty dishes. My mom lives off of Ice Mountain bottled water, so if I'm in a jam, I'll swipe one or two and stash them in my purse. To me, Ice Mountain tastes just like our tap water. The tastes of other bottled waters make me cringe. Everyone has their preferences. Note: If I am in a situation where this is possible, once my bottle is empty, I'll refill it with tap water and use it a few times before throwing it out.