Delaware is an excellent state to start a Limited Liability Company in. Business laws are extremely flexible, and the managing members of a Delaware LLC do not have to be citizens of the state. Forming an LLC in Delaware is also very affordable, allowing you to avail of the protections that a limited liability company provides, without having to break the bank.
Delaware is one of the most popular states to incorporate within, and for good reason. The state has very business-friendly laws and regulations, and is home to over 50% of all publicly traded companies. It can also be much easier to run a corporation in Delaware, especially a larger one, as boards and committees can have alternate members, allowing the business to continue functioning, even if a member is absent. Delaware continue to attract corporate formations, and there seems to be no sign of that stopping.
Non-profits are an excellent way for philanthropists to use the time-tested and efficient corporate structure to further a charitable pursuit. Non-profits are an untaxed structure as they don't make any money, but are run very similarly to a standard for-profit corporation.
Any corporation that is formed to provide some sort of professional service, like medical treatment or financial planning, should be formed as a professional corporation. In fact, most licensing bodies require that professionals regulated by a licensing board adhere to certain statutory roles, and if they choose to form a corporation, those rules require it be a professional corporation.