Comment Kettlebells (Score 1) 865
Buy and learn how to use a kettlebell (from dragondoor), a kb workout can be as short as 5 mins. And you only need one 35# bell.
Keep it in your car. Bring it to the office.
I used to keep one at my desk. During long days when I couldnt go home to train, I would do a 5-10 min set of swings.
KB swings offer you the best bang for your buck as far as any type training goes.
Also.
http://worldsstrongestlibrarian.com/542/how-to-get-stronger-at-work-while-your-boss-isnt-looking/
http://www.russiankettlebells.com/#whytrain
I am not in any way affiliated with these sites...