I made purchases at Overstock. During the visit to the Overstock website i was bombarded with annoying pop up ads that interfered with attempts to complete the transaction. I finally completed the purchases. I noticed afterwards that these same annoying pop up ads followed me to any website I visited. I believe Overstock.com has created this relationship as I did not knowingly agree to receive adds after I left their website. I tried deleting cookies but this did not solve the problem. I complained to Overstock but they were no help. Still working on fixing this mess. User's recommendation: avoid shopping at overstock unless you want your computer contaminated with annoying pop up ads.