Yes, in fact your 5g can be moded it is extremely valuable when moded. Your sound quality can be improved so much by moding it that it is literally the highest quality modible audio device money can buy. However to dyi-mod is very very hard and ordering the work to be done by readwhine audio is expensive. Also you would need to $100 cable to get the sound from it but I do have a 4g imod and it was worth the quality although it does not really batter unless you have good headphones anyways oh and a portable external amp is required with the mod.

However the rockbox part is free and does not have any requirements: http://www.rockbox.org/

*Rock box is an OS change while having an imod is a hotwired 4g, 5g or 5.5g that is capable of producing the highest quality audio of any portable music player but requires an external amp to work.

Rockbox will also allow you to play any type of music file you want and do many other things that you could never do before. Also its navigation system is more logical than the stock way the scroll wheal is used however it is totally customizable.