You might want to look into Priority Pass.

There are two membership plans:

• Standard Membership: $99/year + $24/lounge visit
• Prestige Membership: $295/year with no charge for lounge visits (obviously, the better deal if you use lounges more than 8 times a year)

(See their web site for information about corporate and group memberships.)

But wait, there's more ...

If you join the International Airline Passengers Association:

... as a $299 "Gold" member, you get the "Prestige" Priority Pass, plus all of the IAPA benefits.

... as a $49 "Bronze" or $99 "Silver" member, you can purchase a "Standard" Priority Pass at a discounted price of $75. "Bronze" looks like a pretty good deal; I'm not sure "Silver" adds enough value to justify its cost.

Tip of the day:

You can get a 3 month Free Trial Membership in IAPA.

Disclaimer: I am not a member of IAPA, nor do I have a Priority Pass.