ok, i am working in a bank.
all i can and want to tell you about off-shore banking is, that you have to understand that after 9/11 there is no privacy at all as it once used to be.
every off-shore bank has to have a correspondence bank in order to be able to settle international payments. these payments are settled via a payment network called s.w.i.f.t. after 9/11 s.w.i.f.t. requires you to provide proper documentation with every transaction. this goes as far as that your offshore bank has to fax the detailed documents prior to their correspondence bank in order to get acceptance to settle the transfer via swift. ultimately, you have to provide these documents prior to your bank.
if you can't provide these documents or if there is doubt about the correctness, your assets will be frozen. no offshore bank is risking to lose their correspondence bank connection because of your couple thousand dollars.
s.w.i.f.t. again is reporting the money movements to all governments and ultimately the tax institutions.
so, as someone said: forget about it. offshore banking is cool for tax evasion if you build a more or less complex offshore business structure beforehand. this requires however quite some knowledge and eypertise.
to think that simply having an offshore account is sufficient to avoid taxation is however very very naive and would get you in big trouble.