All bonds are essentially loans, of course, which require collateral. My collateral is both personally owned and highly liquid, in the form of blue-chip stocks. In short, you have NOTHING to worry about.
You may lay claim to your collateral in the form of agreement to my personal information and arbitration via http://judge.me (free) or we can even sign a document drafted by Real Lawyers (tm) -- which you would pay for of course.
Each Eternal Bitcoin Bond costs 1 BTC, and pays 0.05 btc back to you every anniversary of your purchase -- forever.
Fractional investment is acceptable, so long as you understand you will be paying any transaction fees...
You may redeem the bonds for 1 BTC at any time by forfeiting what would have been the interest accrued until that point.
I reserve the right to repurchase said bonds at any time for 105% of purchase price, which would sever the obligation to pay interest on the bonds.
5% APR, keeping in mind many loans here run at about 5%/month interest. That isn't taking into account that principal is returned as well by that date.