I'm not sure if I've had one. I definitely know I've had some lovely ones.
You can write about what would it be like? Imagine your perfect solitary day, and be there with your journal :-)
Here's my outcome: A Perfect Solitary Day.
Writing this post is harder than writing the challenge:-)http://rowlandjones.wordpress.com/2011/02/12/february-challenge-10-a-perfect-solitary-day/