Nirvana is worth every penny
I have been using Nirvana now for several months. I've found it to be the best tool as my GTD system...hands down number 1.
As mentioned it is either five dollars per month or $39 per year. It is worth every penny. I can't believe how perfect the system is for implementing GTD. I can say it is the best $39 business investment I have ever made!
For example, my weekly review went from just over an hour using Evernote to now well under 30 minutes. And because they have an app for the iPhone which works on the iPad and they are web-based so it's available for Droid and PC the access is everywhere.
Imagine sitting at your desk and a thought arises and you simply add into Nirvana at your PC and you've captured that information. Or, you're out walking the dog and an idea pops into your head... you take your phone out...boom, captured. Everywhere you are your capture tool, your GTD system, is right at your finger tips.
My suggestion… skip Starbucks for a week and invest that money in what I feel is the best GTD capture tool on the planet! (No I do not work for Nirvana! But if I did I'd really get on the bandwagon and tell you how wonderful it is).
iPad, iPhone, MacBook, PC; all running Nirvana, iCalendar and GMail
Mastering Workflow (2012 & 2013)