DAL.net adds – and is probably the first network to do this – a “text CAPTCHA” to its nick-registration process.
Their news announcement says that they want to ensure that a nickname and a channel should always be able to be registered first by a human and not a bot.
They do that in response to a trend they noticed where they reportedly have “seen increases in bots getting nicks and channels, holding them, and never releasing them” and continue to say that it’s “not fair to the average person that a botnet gets a nickname before a human does”.
According to the announcement the questions are simple and will be changed weekly – an article in their knowledgebase provides an example of a question that might get used in the registration process:
For example, if the question is “Mark’s name is?”, you would answer:
/NickServ REGISTER <password> <email> mark
The knowledgebase article states that they – for obvious reasons – won’t provide a list with all possible questions and answers but if you should have further questions you’re welcome to /join #DALnetHelp and ask them there.