There is no limit on the number of IRAs that you can establish. However, regardless of the number of IRAs you maintain, you still cannot contribute more than the annual contribution limits:
$4,000 for 2007
$5,000 for year 2008 and beyond
If you are at least age 50, you are allowed to contribute additional amounts of $1,000 for years 2007 and after.
If you decide to establish multiple IRAs, remember that annual maintenance fees that may apply to each IRA. These fees average from $50 to $100 per year.