Regus is best known for their worldwide business lounges, which is a like an office away from your office. They also operate lounges at select airports, and Regus Businessworld Gold membership gets you unlimited access to any of their 1,500 business lounges worldwide located in 600 cities. They're currently offering 1-year complimentary Gold membership to Avis Preferred Service members, which is free to enroll in. Simply register for Avis Preferred Service, then enter your Avis number at the Regus activation page. Since Gold membership costs $49 per month, this is a $588 value for free!!
Regus business lounges typically offer business work spaces, WiFi, refreshments, and beverages. Keep your expectations low for consumables as the token lounge in Sapporo, Japan only offers coffee and tea for free. That's right, Coke and granola bars come at a premium. So while these lounges fade in comparison to international airport lounges, you can't beat free. Airport lounges are very limited, but include Amsterdam and Munich airports. Here is a full list of their lounges.