Don't be fooled by Ponzi's Scams and Other Virtual Currency Conmen: A Cautionary Tale

http://www.financemagnates.com/forex/regulation/largest-bitcoin-ponzi-scheme-uncovered-sec-charges-pirateat40-for-fraud/

T 1333481774 <#me#> k. are you the largest bitcoin ponzi evar?
T 1333486473 <#pirateat40#> +Yes!
T 1333486966 <#me#> Wonderful. Thanks for being hinest, too.
T 1333486979 <#me#> I sent you more bitcoins ;p
T 1333486988 <#pirateat40#> +lol, im sorry to disspoint, no ponzi here. :(
T 1333486997 <#pirateat40#> +But i like to play with people that think I am.
T 1333487081 <#me#> payputs are weekly, next payment is 8th?
T 1333487094 <#pirateat40#> +9th
T 1333487097 <#pirateat40#> +every money
T 1333487099 <#pirateat40#> +monday
T 1333487117 <#me#> you are still very liquid and continue to plan to do this long term?
T 1333487125 <#pirateat40#> +yes
T 1333487126 <#me#> after the difficulty split?
T 1333487138 <#me#> erm
T 1333487144 <#me#> the block reward
T 1333487154 <#me#> i'm looking forward to the 25btc block reward
T 1333487165 <#me#> i have no plans to withdraw, until i do
T 1333487170 <#me#> get my drift?
T 1333487177 <#pirateat40#> +Yup!
T 1333487180 <#me#> ok!

How to spot a Ponzi Scheme (and a whole lot of other scams)

Fools Rush In:
Don't let anyone pressure you into an investment. If you feel you're being pressured, that's all the more reason to suspect that something is not right. Take your time in making your investment decisions. Bandwagon investments are rarely wise in retrospect.

Unrealistic Returns on Investment:
You've probably heard this piece of advice before, but it never hurts to repeat it -- if it sounds too good to be true, it probably is. When you're approached with an opportunity that seems unbelievably amazing, you should be highly suspicious.

Investigate it as much as you can before you fork (fork, get it...) over any funds.

and lastly,

Slow and Steady, Steady and Slow:
As with most scams, the returns in a Ponzi scheme environment don't necessarily have to be unbelievable, so the previous tip won't always help. However, many say that ponzi scheme victims should've been suspicious of how steady and consistent their returns were. They were always moderately good; real investments returns fluctuate.
Devil is in the details: If you do enter an investment, carefully examine what information the company provides. A suspicious lack of details should be a red flag.