I've written about this Sublime Text plugin before but it keeps getting better. Beyond the basics, like sending notes from ST3 to Evernote, this plugin will also list, download and convert to Markdown for editing. Two way syncing and editing of Evernote meta data likes tags is also supported through YAML headers. It also provides support for attachments. Since I last posted about it, now you can add attachments, autocomplete metadata, and search a note. Crazy.
You'll need an Evernote developer token to use it.
Reminded by way of @sublimetexttips