You'll find an interesting report on a recent meeting of members of the cryonics community at Depressed Metabolism. If you're not familiar with cryonics and its relevance to engineered longevity, you might want to read the introduction over at the Longevity Meme before going further - this discussion takes all the basic concepts for granted.
The focus of the meeting was on just one of the number of small and energetic fields of thought that relate to cryonics, in this case how to attempt to preserve assets post-mortem such that you won't be utterly without property when (if) you are restored by future medical technology. A representative quote:
John Dedon is the lawyer that Alcor has hired to create asset preservation trusts for Alcor Members. He said that only irrevocable trusts can be self-settled trusts (trusts where the donor and the beneficary are the same person) and that only 8 or 9 states allow irrevocable trusts.
John was chosen to create the Alcor trust because of his considerable thought and experience with trusts for cryonics purposes. I would still favor South Dakota because (unlike Delaware) South Dakota has no state income tax. South Dakota has one of the longest histories as a state with no law against perpetuities. In my experience, trustee fees are less in South Dakota, and I suspect that the administrative costs associated with paying state taxes is part of the reason.
I note that the cryonics community, rather like the diverse libertarian community, possesses a sizeable minority with a great (and I think misplaced) belief in the power of contracts - of words on paper. You see it in the constitutionalists in the US or the fellows looking for loopholes in tax laws that will enable them to escape the IRS entirely. Words on paper, however, have only as much weight as there are economic incentives aligned with them.
I've discussed this before in the context of setting aside resources for a speculative future revival from cryosuspension via advanced medical technology.
When thinking about these matters, it's best to look at the incentives rather than the details. The trouble with property left undefended, as the ancient Egyptians and every other culture that buried wealth with the dead has handily demonstrated, is that no-one else's interests are aligned with yours. You'd like your wealth - in whatever form it happens to be in - to be your property once more when you are revived from cryonic suspension. Every other person in the world will benefit from taking these resources for themselves while you are out of the picture.
When you place your wealth with a trustholder, you have also given future representatives of that trustholder - and anyone else in a position to plunder or take advantage of the trust - an incentive to see that you are not revived. This is probably not all that important for a small trust held for only a few decades by a large and prideful organization, but the larger the collected mass of trusts and the more time that passes, the less likely it is that the original terms will be honored.
Worse, under the scenario whereby cryonics becomes a large industry - and the practice of establishing asset preservation trusts becomes equally large - those folk being stored are collectively creating organizations that have as much of a financial incentive to use the political process to block revival efforts as they do to play nice so as to obtain new customers. Not to mention being a fat target for others to plunder via that same political process.
(The cryonics providers themselves have the opposite incentives: they want to be seen to provide good service, so as to obtain new customers. They also want the customers who have paid a lump sum on suspension to be revived as soon as possible so as to free up resources for new customers. The former is much more important than the latter).
My own assumptions on the likely time to revival - ignoring for a moment all the slings, arrows, and unknown odds between here and there - are based on revival only being likely when it is also cheap enough for small self-interested groups to undertake. If you look at historical development cycles for new technologies, and take note of where researchers presently are with biotechnology and nanotechnology, someone who is cryopreserved prior to 2020 might be waiting 60 years or more until the economic circumstances favor revival. That's a long time for any agreement to last absent the people who originally signed it, especially when money is sitting around untended.