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Someone built the PlayStation controller PC dongle that Sony refuses to make
(www.xda-developers.com)
If it's free and open source and it's also software, it can be discussed here. Subcommunity of Technology.
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It was cheap too, less than 10 Euros or the like and it didn't have any input latency (at least none I could feel). I remember friends ordering other adapters and some had builtin latency.