Many of us used the yellow rubber duck when we were kids. I believe we still can use the cute gadget now, and not only as a toy, but also a wireless speaker. It’s iDuck.
This fun wireless speaker contains two parts: a yellow duck-shaped speaker and a transmitter shaped as egg. After connecting iPhone, iPod or any gadget with stand 3.5mm audio connector, you can listen to music anywhere through the duck-shaped wireless speaker, even in the bathroom, because the duck is waterproof. Of course you have to maintain a certain distance between the speaker and the transmitter. Two parts are powered by AAA battery. Seven AAA batteries are all you need to feed them.
iDuck waterproof wireless speaker is priced at about $42.5 USD. If you need it for your bath, you can get it at Tradesales.