1. A couple of years ago, got the Amex Gold as part of a promotion (first year free) plus 50K Amex MR points after first purchase. Transferred points to HHonors and a couple of airline partners. (Please send me another one of those offers, Amex

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2. Have used HA's ability to transfer miles in at no charge allow me have a de facto "family account" that way (a la the way bmi now lets you combine all family points into the "Head of Household's" account). Have then transferred HA to HHonors as needed/desired.
3. Have also used points.com every so often, but the transfer ratios are just silly.