If you open minimum sized brokerage accounts (each account say around $5K) outside of the US, you often get access to the primary research done by that brokerage. For example, TD Waterhouse in Canada has good access to TD Securities primary investment research on Canadian companies. Bizarrely, TD Ameritrade in the US does not have access to that Canadian research. This primary investment research has real value, if you plan on investing in individual Canadian companies from your US brokerage accounts.
The IRS has been on the warpath against any US citizen who opens a foreign account. If you correctly disclose such accounts - and if they are a minimal size relative to income and assets - does it increase your audit risk? I want to get a feel for whether the audit pain outweighs the research gain.