Investment bank traders are known to be gutsy and brash, but sometimes their behavior can be downright stupid. Take the crafty cadre of traders at the Royal Bank of Scotland, who for years schemed to rig the global interest rate known as Libor. At least 21 employees at the bank have been implicated in setting the rate artificially low or high to boost the bank's trading profits — a ploy that has cost RBS $612 million in fines.

When they thought no one was paying attention, the bank’s traders sent streams of incriminating (if not particularly grammatical) e-mails and text messages detailing their duplicitous deeds, as revealed by a CFTC investigation. Indeed, it seems to have been almost an open secret that banks were manipulating the interest rates they report to benefit their own trading positions.

Check out some of the most entertaining exchanges -- with some of the juiciest confessions in bold:

August 20, 2007:

Senior Yen Trader: this libor setting is getting nuts [ ... ]

Bank A Trader: im puzzled as to why 3m libor fixing not coming off after the FED action

Bank B Trader: [UBS] is lending dolls through my currencies in 3 month do use him doing the same in urs

Senior Yen Trader: yes [,] he always led usd in my mkt[,] the jpy libor is a cartel now it’s just amazing how libor fixing can make you that much money it’s a cartel now in london [.] they smack all the 1yr irs .. and fix it very high or low


December 5, 2007:

Yen Trader 2:  FYI libors higher again today

Yen Trader 4: [F---] sake. keep ours low ifposs. don't understand why needs to go up in yen

Yen Trader 2: no reason dude[,] [Bank C] and [Bank D] went high yest

Yen Trader 4: send the boys round

Yen Manager: pure manipulation going on


May 14, 2009:

Swiss Franc Trader:    pls can we get super high 3m[,] super low 6m

Swiss Franc Trader:    PRETTY PLEASE!

Primary Submitter:      41 & 51

Swiss Franc Trader:    if u did that [,] i would lvoe [sic] u forever

Primary Submitter:      41 & 55 then …

Swiss Franc Trader:    if u did that i would come over there and make love to you [,] your choice

Primary Submitter:      41+51 it is

Swiss Franc Trader:    thouht [sic] so

Primary Submitter:      so shallow


September 15, 2009:

Yen Trader 1:              can we lower our fixings today please [Primary Submitter]

Primary Submitter:      make your mind up [,] haha , yes no probs

Yen Trader 1:              im like a whores drawers


November 22, 2010:

Senior Yen Trader:      hey think we be able to convince [Primary Submitter] to change the libor today?

Yen Trader 1:              i can try

Senior Yen Trader:      need to drop 3mth Libor and hike 6m Libor he dropped 6m by 2 bps last Friday

Yen Trader 1:              at the moment the FED are all over us about libors

Senior Yen Trader:      thats for the USD?

Yen Trader 1:              yes

Senior Yen Trader:      dun think anyone cares the JPY libor

Yen Trader 1:              not yet [,] i will walk over ot [sic] them