FreedomPop offers its FreedomPop 3-in-1 Global SIM Kit bundled with a FreedomPop Global Unlimited Talk, Text, and 1GB HSPA+/3G Data 1-Month Trial and FreedomPop Premium Plus 1-Month Trial for 99 cents with free shipping. That's a savings of $57 and the lowest total price we could find. (For further comparison we saw a similar bundle that included a Premier trial for $5 shipped two weeks ago.) It's compatible with most unlocked GSM smartphones.
Note: Be sure to switch to the free 200MB/month data plan before your free monthly trials expire; otherwise, you'll be billed $27.98 for every additional month.