I posted this on The Mindfulist but I think it’s helpful, so I’m re-posting it here. It’s a modified-for-being-at-work sun salutation, with the forward fold and backbending action without having to put the hands or whole body on the floor.
Be BAREFOOT or at least in flat shoes. I put a towel under my feet so they don’t have to touch the nasty floor. This instantly grounds me as I spend all day in heels.
Feet hips width apart; inhale and arch into a backbend, raising arms to the ceiling and gazing up.
Exhale into a forward fold, interlacing fingers behind the back.
Inhale halfway up with a flat back, maintaining fingers interlaced.
Exhale and fold more deeply.
Repeat three times… This gives me (and hopefully you) a bit more energy and hopefully helps to fend off the sitting-itis!

Love these “half” salutations. We must remind ourselves to integrate yoga into our whole day, whether in mini asanas like this or in the way we sit, stand, and move.
Heels! The furthest I go is platforms. I posted on high heels (http://yogaspy.wordpress.com/2009/10/30/who-wears-short-shorts-who-wears-high-heels/) and still wonder how women actually walk in them. In the Sartorialist blog, heels are de rigueur among a certain type of female fashionista, but what are the effects on feet and Achilles tendons, not to mention pelvic tilt and spine? You’re an experience yoga practitioner and know how to counteract such effects, but the average chick…
As for practicing yoga on “dirty floors,” what about these FiveFingers (http://yogaspy.wordpress.com/2010/02/02/barenaked-feet/) or those Yoga Toes?
I’m with you on the heels! And being an experienced practitioner does NOT make me immune to anything! I wear a pretty practical pair and ONLY at work. The rest of the time, including my daily lunch break walks, I’m in flats or half-inch platforms. I’m in NYC, though, walking constantly, and no matter what I wear on my feet, everything takes a beating- the few minute walks in my heels can sometimes feel like a break for my legs.
This is one of the reasons why I am SO thankful for my “formal” yoga practice, as well as my sneaky bathroom break yoga and my off-brand toe stretchers.