If the wedding is during daylight hours, my favorite is always semi-formal day wear, also called black lounge. This consists of charcoal DB or SB peaked lapel stroller with buff or light gray waistcoat, checked trousers, long silver tie. This never calls undue attention because those who do not recognize the ensemble will consider it as a dressy odd jacket and those who do will admire you for it. With matching trousers this coat is quite versatile, especially in DB style and can be worn for an evening wedding or any other momentous occasion. Only drawback is the bride will want you if you are not the groom, and every other woman in the house will want you if you are.
can you please provide and example. this sounds interesting