The genuine trade just made me realise that this might be in need of an update. Turns out, 19 days later and we have some work to do.

Prefacing suggestion with Classifieds, in which there are multiple underpriced hams to be found.

http://backpack.tf/classifieds/search/1013/6/0

Priced at .66 =< P < 1 :

http://www.tf2outpost.com/trade/12930429 (Buyer wants one of the hams, perhaps the unique ham)

http://www.tf2outpost.com/trade/12919189

http://bazaar.tf/trade/316508 (Selling three)

http://www.tf2outpost.com/trade/12904624 (Potentially a QS)

Sold at 1 ref:

http://www.tf2outpost.com/trade/12934174

http://bazaar.tf/trade/316993

Potentially sold at 1 ref (No longer in BP, but not traded through Outpost)

http://www.tf2outpost.com/trade/12929637

http://www.tf2outpost.com/trade/12933679

http://www.tf2outpost.com/trade/12925538

http://www.tf2outpost.com/trade/12902872

http://www.tf2outpost.com/trade/12903940

Couldn't find much in the way of buyers for .66

http://www.tf2outpost.com/trade/12902437 (.66 plus junk)

Not 100% sure if this is enough, but it's just to show that .66 is doable, whilst not a quicksell. Please comment if you feel I need more.

Thanks for reading, constructive criticism always welcome : )