for my parents' 25th anniversary, i coordinated a surprise party/luncheon and invited all the relatives, their friends, etc. my grandma helped a wee little bit with the money, but all in all i think we spent about $500 for cake (which was decorated in the same colors and flowers as their wedding cake), food, and a place for the party...we just reserved the back room of a nice restaurant, and paid for buffet-style food. i think about 50 people actually showed up.
i'll never forget that day...both my mom and dad teared up when they walked in and saw everyone. 🙂
i also like ziwi's movie idea very much! 😉