Linksys has an interesting deal to tie in Vonage subscribers with hardware sale: If you purchase a Linksys WRTP54G, their Vonage-enabled two-phone-line 802.11g router, you can receive a total of $130 in separate rebates with a trade-in.
Here's the run-down: buy the WRTP54G from a participating merchant with your intent to sign up for Vonage's voice over IP service. The merchant will offer $20 off as a mail-in or instant rebate. (Amazon.com is offering it as an instant rebate, bringing the initial cost down to $110 from $130.)
Next, fill out the $10 Linksys mail-in rebate for the unit itself. The merchant will include the form or allow you download it to print out. This $20 and $10 rebate don't require the Vonage purchase, but it would be odd to buy this model without planning on using Vonage.
Signing up for Vonage brings a $50 mail-in rebate after 90 days of service, while trading in any older wireless router (no particular types are defined) adds another $50. The Amazon.com downloadable form lets you apply for both rebates at the same time.
That's a lot of hoops to go through, and it's not quite free--you'll spend about $5.00 on postage and photocopying, and possibly an hour or two or your time filling out forms and mailing items.
The router must be purchased by July 23 to qualify. The $10 rebate must be postmarked by Sept. 21 to qualify, while the $50 or $100 form must be postmarked no later than 60 days after the date of purchase on your invoice.