Do you have pictures of your time working with each other? A scrapbook/photo album of those years would be nice gesture. If you don't have multiple photos, one really nice photo in a frame is also nice.

Maybe an experience? Is there something you've talked about doing with them but never got around to actually doing?

A homemade frame with a nice picture/memory! 

We've worked together for 15 years and she's (the boss, 55) more like family than an employer. Sadly after 85 years of business, the current owner is being forced to shut down and I would like to get her something that commemorates her time there and something to remember us by. Any ideas? Thanks!

[HELP]gift ideas for my Boss on our last day of business[F, 55, up to $200]