Note that many websites have their own advertising, unrelated to adware.
Mirar Toolbar is a Internet Explorer toolbar that has been reported to stealth install.
"The Mirar Toolbar provides content relevant information while you browse the web.
Finding pages of similar topic and interest to the page you're on it shortens the time required to find the info you need."
This toolbar will go beyond simply redirecting your searches from search strings inputted in search engines. It matches terms found in urls and redirects your webpage to their affiliates. For Example: Visiting spywareguide.com has been seen to be redirected to winantiviruspro.com (A known rogue antispyware application).
Mirar has been installed with exploits and can be installed from large bundles of ad-ware without user consent.