Because a girlfriend can only have so many "hug coupons", mix things up this year with one of these three Valentine's Day gifts which, when given, have been scientifically proven to lead to sex. Look it up. (Don't look it up.) L. Makai Commuter CollectionAvailable in sterling silver or gold vermeil, these locally made freeway sign-shaped pendant necklaces (which start at about $70) are the perfect Valentine's present if your girlfriend always talks about that one road trip you guys took down Route 1 and/or drives trucks for a living.Mix and match at LMakai.comConscious BoxAssuming you ever want to get access to hers, gift your GF a Conscious Box: a subscription service that costs about $20 a month from a former fashion designer that delivers eco-friendly products once a month, including everything from lip gloss to chewing gum. Also: there's a vegan box and one that's gluten-free.You can get it at ConsciousBox.comCookie Casa BakeryThis sweet sweets shop's opening a brick & mortar on Beverly on Feb 11, but they're now taking pre-orders for V-Day (with cookies starting at $18 a dozen, and cupcakes, $33), including homemade peanut butter cupcakes and a vanilla cream-stuffed molasses-cookie sandwich that's probably baked slooooow.What's in a crack cupcake? Find out here.