Hey darwin,
Hope you had your flame suit on for that one. I have to agree with those who have already b*tched you out, but I do want to give you a few things to think about before going down this road.
After a job change last year, I now work for one of the biggest banks in the US. Bank employees are specifically required to take training courses on how to spot attempts at money laundering, tax evasion, and other activities (legal or not) that could raise suspicions. In fact, the passage of the Patriot Act places a whole new set of requirements on US banking institutions regarding even relatively modest transactions. Banks are extremely eager to comply with these regulations, as there have been cases that have led to multimillion dollar penalties and criminal charges against staff who have neglected to report these types of transactions.
You may have already thought of this, but how were you planning on getting that money into your offshore account to begin with? Most likely, you'd arrange a series of wire transfers from your client's accounts to your offshore account. The client's bank must report details of the transaction (dollar amount, payer, receiving bank and account number, etc) to the feds. And, unless your account is in a "noncooperative jurisdiction" (and, no, Switzerland is not on the list), that foreign banking instituition is happy to give details regarding your offshore account ownership to the feds. They match these up, and investigate all transfers over a certain dollar amount, or series of transactions that add up to a certain dollar amount.
Why are the feds so interested? Traditionally, they've been tracing money to crack down on the drug trade, tax evasion, or other illegal activity. These days, their watching more closely than ever to try to track money that might possibly be funding so-called terrorist organizations.
The bottom line is that, unless you have a really complicated scheme in mind to illegally launder your money into that overseas account (let's call a spade a spade), you will get caught. And I guarantee you will wish that you had simply paid your taxes to begin with.
--Dan.