Also important to note these are almost all fully funded companies with solid dev teams. I've had great offers that just never worked out due to fit (or rather lack of passion from the dev teams).
I've thrown the offer out there on several occasions but it's always refused or delayed to the point where contact drops. One time the senior engineer told me my offer to come in and code on my own dime was "nonsense" and If I knew better I wouldnt be offering my work for free, because that would hurt the "startup economy".
My faith in the NY Tech Scene is pretty much non-existent to the point I'd rather make hourly wage in manual labor and hack on projects in my own time, as opposed to burning myself out around people like noted above.
--edit-- Which is exactly what I do
