I don't have to try too hard to not get 'caught'.
I don't use pony wallpapers, mostly because I prefer having it space-y or something.
I watch/browse after everyone is asleep, mostly because I like to be productive during the day.
The pony music I listen to is in a youtube downloader app on my IPod that no one would think to open, and my IPod is locked, although any fans of a certain BBC show could get it.
Although I try to justify hiding it I still do it on purpose, it's just in my nature. I'm one of those people that waits for others to make their move first.