We hope you're wearing green today, because otherwise we're going to approach you, think better of bringing up pinching of any kind in a workplace setting, and then back away awkwardly in embarrassment. Nobody wants any angle of that to transpire. Instead, we propose celebrating St. Patrick's Day.
When it comes to ringing in the now heavily-commercialized feast day commemorating the 5th-century's arguably most well-known Patrick, there are a number of traditions for both the Irish and non-Irish to partake in. Our favorite tradition is correcting drunkards who incorrectly link the Blarney Stone to St. Patrick's Day. It's a superficial connection at best and an ignorant confluence of Irish traditions at worst. Seriously, put down that green beer and read a Wikipedia entry once in awhile (we wear football pads when we do this, by the way).
Happy St. Patrick's Day!