In November, 2009, my wife and I had 182K miles and points across all programs. Since then, we've earned 4.7 million points and redeemed 1.5 million without a single non-award flight taken. Thanks, Flyertalk.
@ factory81: I make 5 figures (not 7), and spend about 60 nights a year in hotels/B&Bs (all leisure). It's all about credit card bonuses and promos.
Our current (approximate) totals:
AA: 920K
BA: 370K (plus two 241 coupons)
DL: 750K
UA: 306K
US: 460K
VX: 50K
AMEX: 122K
Hotels
PC: 116K
CC: 190K
*W: all gone (lifetime Gold on AA)