The iRiver Story allows the user to install their own fonts, these fonts can truetype fonts (ones with the .ttf extensions).
To install the fonts, connect your iRiver Story device via your USB cable, then select mount/drive etc..
Then browse via your explorer/finder to the font’s directory and just drag/drop/copy the .ttf to it, then disconnect.
Then goto ‘Settings/Change Fonts’, then when goto your Diary/Memo the font will have take affect.
Unfortunately I can seem to make it work for pdf files!
Sample fonts i played with are: