Evernote is a great app that I use daily, but it's missing a key feature such as mind mapping.
I use Archi. Its not a mind mapping tool per say, but easily re-purposed as one, as it shares the fundamental features. The reason I choose Archi is because it's free, available on many platforms, light weight, fast, easy to use, has strong generic types following TOGAF/Archimate, and saves in a simple XML native format.
I also use Archi at my day job as an Enterprise Architect :)
I follow two workflows.
1) Some notes, belong in Archi. An Archi document can be easily attached to an Evernote note and filed as an attachment.
2) Switching from Evernote to Archi and Archi to Evernote is analogous to switching between mathematical co-ordinate systems to simplify a formula, also giving a vantage point for a different perspective. Archi also supports JasperReports. Further allowing exports to Adobe:PDF, Microsoft:Word, Excel & Power point, and even the Open Office Equivalents.
For the 2nd workflow, Since both are based in XML, I use XSLT to transform from .enex to .archimate formats. There isn't a 1 to 1 translation between the two, more like art then science, and potentially dependent on the notes content. I'm constantly editing my .xslt in tools like notepad++ and xsl:easy
Actually once comfortable in the process, you would be able to convert from .enex to .enex, or any other xml based format. You could build a .enex to .docx and convert your notes to documents that Microsoft Office , Open Office or even Google docs supports.
Notepad++ has XML syntax highlighting, and an optional plug-in called "XML tools". Under XML Tools > XSL Transformation, will prompt a dialog where you can transform the current file using a xslt document.
xsl:easy is a nice Drag & Drop GUI based xslt editor.