Flip has just launched this morning a No Cap Data Pack for $35 per month when you get a homeline for $49.95. So in total you're looking at $84.95.
This new pack is unmetered, rather than unlimited as there is a fair use policy - see below
Flip’s unmetered data pack (called ‘No Data Cap Pack’) heavily limits the speed of peer to peer (p2p) downloading at all times to protect overall network performance. This will include other web downloading where appropriate.
At Flip's sole discretion excessive users will be notified to reduce their use, then if no suitable change, removed from this pack.
All other fun stuff like streaming, browsing, gaming and internet calling runs at full speed.
We've also put together a list of limited technologies: http://support.flip.co.nz/entries/23025086-no-cap-data-pack-list-of-limited-technologies
So as you can see, this pack isn't about massive downloading/leeching. It's about heavy use of the internet in general of legal content. Good for flats, families and anyone that simply uses the internet a lot.
I'm around all day to answer questions if you have any.