You didn’t say what time frame? You can do guv’ment debt at 30 years for 3.76% now…

http://www.bloomberg.com/markets/rates-bonds/government-bonds/us/

I think this would be rather easy with corporate debt though. Some that pop out are MSFT, JNJ…AAA rating…I doubt you have to have that…Just make sure to hold to maturity:
http://reports.finance.yahoo.com/z1?b=1&cpl=-1.000000&cpu=-1.000000&mtl=-1&mtu=-1&pr=0&rl=1&ru=1&sf=y&so=d&stt=-&tc=1&yl=-1.000000&ytl=3.000000&ytu=-1.000000&yu=-1.000000

Long term bonds are risky since everyone thinks rates will go up…but we could just be like Japan for the next 20 years too…who knows.