Here's a modest proposal:
Forbid federal agencies from 'purchasing' each others' debts!
The BIG BIG BIG one is the so-called Social Security "Lockbox". All those trillions of dollars of 'savings' have really just been used to prop-up our deficit spending, through the SSA 'purchasing' Treasury bills. Instead, I propose they be required to only purchase home loans. In this way, the "lockbox" would actually own tangible assets and would also provide a steady market for home mortgages.