Panchabread Nexus. Mashed two types of decks together. Works a dream.
The aim of the deck is to set up a rig consisting of 2 Panchatantra, 1 Gingerbread, 3 Rabbit Hole, 1 Security Nexus, and at least 1 R&D Interface. With econ coming from Underworld Contact, Daily Casts and Professional Contacts or Magnum Opus, most servers are incredibly cheap to access. Panchabread is so good at getting in anywhere, and if you're playing against decks that already have a lot of tracer ICE like New Angeles Sol, you're in even more luck.
The main problem I had with the classic Nexus Kate build was that I rarely had the breakers I needed to access servers in the early game. The suite also took up a lot of deck space and made fitting in them valuable Diesels difficult. I was drawing too much and not applying enough pressure. Using Panchabread gives you a fighting chance because you can begin to threaten early one-deep (or even two-deep, depending on the corp's econ) servers. Scrubber is MVP against asset-spam corps and totally worth the 2 pips - it makes trashing PAD Campaign for 2 and Adonis Campaign for 1 a lot more appealing. John Masanori is also brilliant and helps you be more offensive without giving up those valuable draws.
Be prepared to let the first agenda or two pass by if doing so will drastically set back your rig development. Clot will buy you time, and poking around with the aid of HQ Interface is worth doing.
Magnum Opus can be a little clunky and is really only there to help your early game economy if you don't have the to install your Nexus. A lot of games clicking for ProCon will be more utilitarian than using Opus. You don't need to rely on it every game, and don't hesitate to trash it if you need that back.
Deus X might seem like a silver bullet against Jinteki but it also doubles up as an emergency breaker when you name AP with Panchatantra! It can catch the corp off when you're low on econ and in a pinch.
Standard ETF is easy for this deck to beat but NEXT ICE suits can be tough. They can climb over Panchabread if they have 4-deep servers, but they also rely heavily on code gates so ZU.13 Key Master is a nice backup that has saved me a lot. The worst matchup in my experience is Blue Sun - if their econ gets too far ahead of your own they can switch off Nexus which hurts a lot, especially if you have John Masanori installed - that's two tags you've just took. 4 and later you're feeling a little deflated, or if you ran third click, just hope that you aren't dead next turn.
s/o to Pinkwarrior's fantastic Nasir deck (http://netrunnerdb.com/en/decklist/31591/into-the-nexus-leeds-store-championship-3rd-place-) for the Scrubber and Deus X idea!