This plugin adds a sidebar widget that is similar to Etsy Mini but allows control of styling and other parameters.
At the time I wrote this plugin another etsy sidebar widget was available. However, it didn't meet my needs because it only allowed you to embed Etsy Mini code. Functionality which could just as easily be obtained with the default 'Text' widget.
Etsy Mini uses an iframe or flash object. In either case there is no easy way to control the styling. Also, you must go to your etsy account to generate new code if you want to change the basic layout. This widget allows complete styling and an equivalent number of layout options in the widget configuration.
Yes. By default, a json cache file is stored in the system temp directory. The cache is refreshed every 6 hours. You can change the cache location in the configuration window.
The wordpress object cache is not enabled by default. I choose not to use it because I wanted the plugin to be as easy as possible to install.