There has been talk about the S Pen supporting Bluetooth this year, allowing users to employ the accessory as a wireless speaker. That would require the S Pen to run on batteries, which could make it a bit thicker than in years past. Another possibility is that the S Pen could add Bluetooth, a speaker and a microphone in order to make phone calls, as long as it remained in close proximity to the Galaxy Note 9 handset.
One interesting concept mentioned would allow a user to "write" on a piece of paper using the S Pen. Since the S Pen is inkless, the words "written" on the paper would appear only on the Galaxy Note 9's display.

Intriguing tweet from tipster Ice Universe hints at compelling features for the S Pen accompanying the Galaxy Note 9
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