The following business offer free wi-fi for customers in the Cairns district:

Cairns Library - offers connection to Cairns Community Wifi - 100MB download limit per day.  If a Library member you get 200MB. Available from Library on Abbot St and in some areas around the Esplanade

Xtreme Travel -  A hub that provides a multi-street FREE Wi-Fi access along Abbott street from Aplin to Shields and beyond the Cairns esplanade lagoon. It is located opposite the Night Markets at 129 Abbott Street Cairns City.  Xtreme travel  the first internet lounge and travel desk to provide IPADS and FREE high speed internet and discount tours.

Visit Cairns  - Offers free wifi for travellers staying in Holloways Beacyou might be able to get signal staying at Machans Beach too.

The Tour Company - Cairns Visitor Information an Booking Centre.  Here you get FREE Unlimited WiFi and can also borrow an iPad to use for FREE,  the staff are also very handy for all the info you need on travel in Australia.  Located at Shop 5B 103 The Esplanade, Cairns City (Between BarnacleBills and Movenpcik ice cream) Look for the big flag with the big blue i .

12 BC or Twelve BC - Coffee shop at City Place. Cnr Shields and Lake Street. Free Wireless plus some of the best coffee in town as well. Coffee about $3-$4. Have cafe type meals and snacks.

McDonalds - As they do countrywide free wi-fi is available at all their restaurants. McDonalds is located on the Esplanade on the corner of Shield Street in downtown Cairns. There are several other outlets in suburban Cairns.

Blue Sky Brewery - They also have some great deals on snacks like $2 Taco Tuesdays, and local brewed ales of course.

The Chocolate Room - 11 Grafton Street (near Shield). 

Hot Air Balloon Cairns - has free wifi on all of its 6 transfer buses from Port Dougals and Cairns daily and with an hour to travel along the way you can easily catup on emails, Facebook and post images as you transfer to the daily balloon flights  

Accommodation with Free Internet - Links through to Trip Advisor Hotel with  Free Internet Pages.

You can check with other hotels if they have free internet. Reviews suggest for eg that Novtoel Cairns has free wi-fi in pool bar area. Current Hilton promotions offer free wi-fi in their business centres.

 

For extended trips purchasing pre-paid system may be worthwhile. Hotel rates can be expensive and may justify the cost of a modem. The best coverage is offered by Telstra if travelling to remote areas but if you will be staying in major cities where coverage is good anyway then please shop around for better deals. Any technical questions please visit whirlpool forum. Many tech savvy people there to assist..