PRO have made a new stem for Di2 integration, but I think it's pretty new and not commonly available, don't really know what it does...
http://www.pro-bikegear.com/global/en-gb/road/stems/PRO_SS_VIBE
I think they have bars too. They deffo have an XTR di2 pre-drilled riser bar.
@Howard started
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PRO have made a new stem for Di2 integration, but I think it's pretty new and not commonly available, don't really know what it does...
http://www.pro-bikegear.com/global/en-gb/road/stems/PRO_SS_VIBE