Perhaps there is a checksum internal to the actual public address string that I was unaware of.
Several of the characters inside a Bitcoin address are used as a checksum so that typographical errors can be automatically found and rejected. The checksum also allows Bitcoin software to confirm that a 33-character (or shorter) address is in fact valid and isn't simply an address with a missing character.
My bad. And I was being so careful all of these years.
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@cypher: You either can can get at all your Bitcoins with ease in which case you are prone to certain types of extortion, or you cannot.
If you only have a couple large to your name (or, arguably, have been wise enough to keep your involvement in Bitcoin top secret) then you probably have less to worry about on the more fringe types of attacks (or what are
currently pretty rare attack surfaces.) Someone who has more would be wise to be more careful. Just like those who have a noticeable number of KR's.
I (seemingly alone, but recently having more company) am also worried about software and hardware exploits and factor them into my security plan. Sure would suck to have your Bitcoin lifted by an 'angry bird'...or a video driver. I don't even use Window or Android to check my real mail any more, much less have the ability to access private keys. This after some bizarre behavior from my phone.
