So here's a possible situation: you have hotel points, you want airline miles. As a concrete example, I have a lot of Choice points and I might want some Northwest miles. The exchange ratio is 5000 pts -> 1000 miles.

Suppose I have 125,000 points. I can turn them in for 25,000 miles.

But NW is running a promotion, and a hotel point-to-miles transfer gets a 1000 mile bonus. (I've been using this promo with hotel stays to build up the miles).

Anyhow, my first solution is to transfer the 125,000 points into 25,000 miles and get a 1000 mile bonus, for a total of 26,000 miles.

It just struck me, that I could transfer 5000 points into 1000 miles, and get the 1000 mile bonus, for a total of 2000 miles for that transfer. If I do the same thing every day for 25 days, I should get 25 1000 mile bonuses, for a grand total of 50,000 miles at the end of the 25 day period. Effectively doubling my result.

Obviously, the technique depends on the exact promotion involved, but I just thought of it. Please don't tell me everyone's been doing this for years, and why am I so slow?