Reply #10: Here's a story I read years ago about 2 US citizens whose boat needed repairs in Cuba,

[Judi Lynn]

who had to fight for their lives legally in the US when they got back:

VICTORIES VS. THE TRAVEL BAN

~snip~
Kip (73) and Patrick (58) Taylor of Michigan sailed to Cuba in 1996. Knowing that U.S. law prohibited spending money in Cuba, the Taylors stocked their sailboat with enough provisions to last for the duration of their three-month trip. While sailing back to Florida, their boat was caught in a storm and struck by lightning, destroying their mast. After being rescued by the Cuban Coast Guard, the boat was towed back to Cuba. When the Taylors applied to the U.S. Treasury Department for permission to repair it, they were told to abandon their boat and leave their two dogs in Cuba. After weeks of attempting to negotiate, and unwilling to leave behind their dogs and a sailboat worth more than the costs of repairs, the Taylors fixed their boat mostly by themselves and with the help of visiting sailors who donated parts.

Upon their return to the U.S., the Taylors faced a civil charges from OFAC for disclosing that they gave a band-aid to a Cuban cook who had hurt his finger. They were charged with providing "nursing services to a Cuban national," which is forbidden under the embargo. For the next four and a half years, the Taylors, who are on a fixed income, were unsuccessful in requesting a hearing or a reduction of the penalty. In 2001, the government froze Patrick Taylor's tax refund, which he needed to pay for urgent medical care, and applied it to his fine. In 2003, the Center for Constitutional Rights (CCR) filed suit claiming that the Taylors were unfairly penalized under the Cuba embargo regulations. Lawyers also say the two were not informed of their Fifth Amendment rights which protect them from self incrimination. The suit was eventually settled.More:
http://www.righttotraveltocuba.org/defending/victories_vs_travel_ban