MLP

Master Limited Partnerships (MLPs) own and operate natural gas and crude oil pipelines and storage tanks, and periodically distribute their cash flow to investors, resulting in 5% and over yields.

Here is a nice article from 2012 :
http://etfdb.com/2012/guide-to-mlp-etfs-and-etns/
Of interest:
AMJ and AMLP are the biggest
MLPL is 2x-leveraged of AMPL (also similar to MLPI)
YMPL   in addition to holding royalty trusts and energy  firms, YMLP also makes allocations to companies involved in marine transportation and the production and marketing of other natural resources including timber and fertilizers.
 MLPG is mostly nat gas
EMLP is actively managed

http://stockcharts.com/freecharts/candleglance.html?AMJ,AMLP,MLPI,MLPL,MLPN,YMlp,MLPW,MLPY,MLPG,MLPA,EMLP|B|P5,3,3
AMLP pf targets 19.55 and 20.50
AMJ pf target is 59.40, but now it seems to target 43.  Tried to buy on 7/9, but got this message: " This security is restricted from online opening trades or restricted to closing trades only." What...?
MLPL targets 78ish
MLPN targets 36ish
Overall its 20% up from here for this group. I will be looking to get 2 out of 4 above sometimes next week.

Finviz doesn't have much info, and none for AMEX listed etf's (YMLP, MLPA, EMLP) . Here sorted by liquidity. Note that leveraged MLPL is the best performer with highest yield.