[nznog] RBL's used

As the amount of spam grows as the internet grows bigger, using RBL's is growing as well (to try and stop/slow the spam). I am wondering what RBL's other ISP's/Companies in NZ Use? There are quite a number (of RBL's) but a few can't be used as they still have Xtra's Network in them (for "Sueing ORBS" they say), but the best I've found so far has been http://relays.osirusoft.com. Can anyone suggest a better one/comments/pitfalls on using RBL's for slowing down spam. Thanks Craig Whitmore Orcon Internet http://www.nzdsl.co.nz