Now I'm thirsty. Whether you're looking to add to your collection or need a starter bottle, reusable water bottles are a simple way to help the environment, save money and stay hydrated. The main reason I carry one is to help eliminate the use of plastic — watch the documentary Bag It and you'll want to do something. Here's one thing. In a city full of fitness fiends, we have an extensive selection. Here's a guide to the city's coolest, all BPA-Free (BPA is a chemical compound used in manufacturing polycarbonate plastic and epoxy resins; it's an endocrine disruptor that mimics estrogen).

The hands down largest selection is at Sports Basement. I went to the one in the Marina and spoke with a sales associate for some scoop. She said an emerging trend is glass, hence the silicone-covered polka doted 16 oz Lifefactory bottles. These are tempting, in their bubbly colors, but I'm looking for something smaller and sportier. I couldn't help but be allured by the rack of rainbow Klean Kanteens. One of my favorites, Kanteens come in all shapes and top styles. I recommend the stainless steel ones for dudes. But the bestseller remains to be the classic Nalgene; you can find bins filled with juicy options.

For something with a filter — ideal for travel through murky waters — American Apparel sells Water Bobbles. From $12-$15, these clear baby bottle-esque bottles are hard to refuse. Not ideal for the car because they won't fit in a cup holder, these are best equipped for travel or the office. The carbon-based refillable filter removes contaminants from tap water and these are Made in the USA; good luck choosing a color, I recommend the yellow for an upbeat splash of sunshine.    

REI has another vast selection; less frills, more function. CamelBak, Nalgene, Klean Kanteen, Thermos, Siggs, Liberty Bottleworks, and all the accessories to go with. Sleeves, various top styles, slings, splash guards — your water bottle is good to go. The handsome REI-branded Thermos and the 64 oz stainless steel Klean Kanteen are the studs here.

For some old school flavor, Adidas Originals has flower powered steel water bottles in classic blue and white colorways. The top has a handy key holder and extra straws can be found inside. At $20, these waterbottles bring retro appeal to water bottle world.

The most feminine options are at Lululemon. Branded Siggs in tropical colors tugged at my yogastrings. A Sigg with a trippy smoke print stood out. If you're a runner, you'll appreciate the "I Heart Running" bottle. Different tops and sizes are available. When in doubt, match your Lulu bottle to your Technithong.

Meet the newest member of my water bottle family: Klean Kanteen's 27 oz classic bottle in Glacier White found at Lombardi Sports. Lombardi's selection was wee, but they had the one. Why white? Because it's just begging to get dirty.

Samantha Durbin (sami.7x7@gmail.com) is a lifestyle writer who honed her blogging skills as Editor of FabSugar.com. Samantha graduated from The Fashion Institute of Technology, also writes for San Francisco magazine and Gilt City, and shares her musings via her poly-blog network, led by SFonFire.