Did some more trading last night (I know, big surprise) The villager who used to have 10 Emeralds for a Clock as his last trade has now upgraded to takeing 1 Written Book and giving 1 Emerald. He is now an extremely profitable source of emeralds. Start farming that sugar cane and killing squid (if anyone needs leather, let me know.)
The villagers who want cooked fish also accept cooked salmon. Since fish takes so long to catch, I'd advise only trading fish with the villager who has it as the last trade, only when all his other lucrative trades are exhausted (coal, beef and pork, if I recall correctly), and then only the one trade needed to reset his other trades.
I did some number crunching on buying Bottles O' Enchanting. For those that haven't seen this rare item before, it's a thrown potion that breaks into experience orbs when it hits, releasing 3 - 11 points of experience. One of our villagers, very nicely walled in so that he cannot move, trades 1 Emerald for 4 Bottles O' Enchanting. When I tested, he sold me 12 of those trades before refusing more, 48 bottles. I then had to make a 3 emerald trade in order to reset. (I don't yet know if 12 trades is a set amount or if it varies.) Assuming an average of 7 experience per bottle, that means each emerald buys 22.4 experience. At beef prices this is roughly 1.5 exp per piece of beef. Cooking beef gives 0.35 experience per operation.
So, if you're playing the enchanting game, and are willing to run over to the village do some trading, then it's much better to trade your beef to emeralds and then to bottles o' enchanting. Admittedly this doesn't take into account the time it takes to fish up 9 fish to reset that trade group, but I'm going to assume it doesn't ruin the deal, since it brings it it's own emerald and fishing experience, etc.[DOUBLEPOST=1388606444,1388606339][/DOUBLEPOST]
Yes, but we're talking about useful stuff.