May be it is long running, but I only noticed today that existing customers can get this offer.
Existing electricity customers can get this offer by adding broadband.
New customers have to add electricity + broadband
Terms, eligibility and early termination fees apply(mercury.co.nz). Prices may change during the term. Router included with wireless broadband plans only. For fibre broadband, bring your own router, or purchase for a monthly payment over 2 years. Broadband plan availability may vary.
Been on this for last six months (existing customer). Been good overall.