How much capital do I need to retire comfortably on ?

[Beagle]

Just thought it might be a good idea to float this as a subject seeing as that's the reason many of us invest !!

I am sure many of us readily recall that famous line from the movie Wall Street when Bud Fox asked Gordon Geeko, How much is enough Gordon, How many Yachts can you waterski behind ?

So how much is enough ?

First up its clear everyone will have different idea's and different goals and aspirations regarding their lifestyle in retirement.
Secondly everyone will have different perspectives on when they want to retire and will have varying idea's about their likely lifespan when they retire.
Others will continue to enjoy working part time in their career or their business even after retirement.

There's also the open question of whether the Government will have sufficient funds to keep paying the superannuation when the huge tidal wave of baby boomers retire.
Will they bring back some sort of National Superannuation surtax like in the old days or is this such a huge political hot potato no party would dare take a position that would offend the grey tsunami ?
Will there be some sort of wealth or inheritance tax in the future ?

So how does one go about some sort of logical reasoning in terms of retirement planning ?

Lots of questions and I'd love to know others plans but for what its worth here's a starting point for consideration.

If one were to take the viewpoint that they'll work on until they're say 70 (at least part time) then how much capital should one have to live comfortably, (talking today's dollars) ?

Does one take the view that $1m should cut the mustard and with a well diversified portfolio of stocks and bonds earning an average return after tax of 7% should be possible, $70,000 per annum.
Add in national superannuation and some part time work or rent from a rental property or two and assuming your mortgage free on your house then all should be good right ?

Thoughts ?