How about a short sound that can play when you recieve a new PM so you don't have to keep refreshing just to see if ya got a new one... you could make it to where the sound is off to start but members can choose to have it turned on if they like.
then maybe make 5 different sounds so there's a variety of choices... or even make a sound shop where members have to use dragon resources to buy them (including to get their first sound be be able to use this option)... or even make it cost dragon coins if you want.
I think if you make a SHORT limit to the amount of sounds there are, it wont cause much problem
