There's an old thread about this somewhere (probably more than one) which had some crackers in it
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I used to give them separate names, but like SR above it works better for me if I don't know which is which so I save them all as either 'Can't Read 1' (etc - I'm up to about 50 now), '[City Name]TW/NS' depending on where I was, 'Mr Midnight' for the silly o'clock ones or just plain 'No' which covers everything else including the abusive ones - apart from anything else I'm never tempted to answer them then.
I do have a few saved under their opening lines if they've sent silly texts - there's 'I'm 16 and have ?300', 'I'm 52 babe', 'i want big tits' and so on; I had a lot more before I had my work phone nicked but they're all in my computer somewhere. I've got a fair few under 'cheapskate' or 'haggler' too just in case they decide to have another crack at it.
About the only numbers I don't save are the nice people who've been once or just occasionally - I do hang onto good regulars ones so I know to answer even I'm not taking calls otherwise, but my system for saving them is so cryptic it makes me sound like Rainman
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