I've always found good ol' Doc Martens to be the comfiest, and the easiest to get away with in work uniform terms. An extra insole added to any footwear is also my latest thing, standing for long periods .. I'm getting to old for that shit o.O
Ah yes, but DM's, good ankle support etc - it's how they came about originally.
Lots of styles, patterns etc and some of the faux Docs styles are also pretty sweet .. and cheaper. Back to foam insoles tho - they rock imo