Here at Divester, we don't usually encourage you to put a radio in the bath with you, but we don't usually see many waterproof radios, either. This floating, rubber cartoon-y sub radio features a waterproof speaker, an antenna, full frequencies auto-scan function, and all the buttons on your "regular" radio (think: power and volume buttons).
Available in either black or yellow, the manufacturer claims the radio is suitable for ages 3 years+, but you can tell people it's for adults, you know, since it's a sub. The radio will set you back about $30, which is a very reasonable price, I think, so you can brag to your friends about the personal sub you own. Drop it in the pool with your remote-controlled shark and let them battle it out.