There are already such devices on the market...
Posted Nov 20, 2011 8:04 UTC (Sun) by khim
In reply to: The Journal - a proposed syslog replacement
Parent article: The Journal - a proposed syslog replacement
What you are describing looks awfully close to the "P33 JailBreak dongle".
PS3 Jailbreak works by overflowing receiving buffer in the PS3 so it needs to emulate four or five (depending on Jailbreak payload) USB devices, return bogus information with jailbreak code, etc. Significantly more then what your "logging device" should do. These devices price is starting from about $10 retail and this is with tiny runs so not much of the "economy of scale". More expensive ones (in the aforementioned range of about $20) may even emulate USB stick to make use after successfull JailBreak more pleasant!
In short: what you are describing looks perfectly doable.
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