I use an extra-small Orvis nylon embroidered collar for ID purposes:
Personalized Dog Collars / Personalized Adjustable Dog Collar -- Orvis
Bella can't wear tags on her collar--she chews and obliterates the information. Between the embroidered collar and her microchip, I think she's adequately covered. I keep her rabies certificate and tags in a special drawer at home should I ever need them. So far, I've only needed them as proof of vaccination for groomers.