I use my Cub Cadet GT2544 which is a bigger, more powerful tractor, but with a small deck to cut as close as I dare. I have slid it in twice and had to winch it out with the ATV. This is always good to get the heart racing!
I also use a push mower and string trimmer to finish up, but it is a pain and takes me longer to trim than it does to cut the rest of the yard.
Swisher makes a tow behind offset string trimmer that looked like it might have done the job. It was called a PostMaster and was intended to get you in close to a fence row. I could not make a decent deal with our TSC store and gave up on it. Unlike a regular offset tow behind, this thing had a set of small wheels that would stay up on high ground and leave the trimmer portion floating out to the waters edge.
http://www.swisherinc.com/postmaster.asp
