Of course X never, ever marks the spot and most hunting takes place in the library if my Indiand Jones quotes serve me well. But golly-geewiz! This is an enticing adventure! I'm a sucker for a good mystery and this one is of the highest caliber. Believe it or not an interesting and accomplished old man hid a treasure chest in the Rocky Mountains somewhere and wrote an ambiguous poem which, if interpreted 'correctly' should lead the hunter to the cache. He posted it on his blog and printed it in his memoir. So its public domain and has many people around North America dedicating themselves to X. Just reading the banter between treasure enthusiasts and theories to where the stash may be is immensely entertaining. It's hard not to become engrossed in the mystery or at least be mildly tickled by the intrigue. Have a read its a great story at the very least.
Oh and one last thought. Why hasn't anyone made a treasure hunting game? I mean we've all found 'booty' of at the very least 'loot' in many games, but i have yet to see an actual dedicated treasure hunting game. Where you have to research, decipher maps and brave the wilderness. I guess Tomb Raider was close but i'm thinking something less about killing people. Just an idea.