If your hobby is genealogy you may like mailing lists where you get emails on a topic which could be a surname or an interest such as Irish genealogy or even as local as Co Limerick genealogy. Mailing list (sometimes called maillists) work by sending a copy of each message to posted to all subscribers. Some lists are very small and some are large.
Generally on lists, it is good practice to subscribe and then just read messages for a week or so before you post. Get a feel for the list. And read the welcome message you get when subscribing. List owners often describe the type things that are allowed and not allowed on their lists. Mail lists are a very powerful way to get your message in front of many people who may be able to help.
Learn the types of things that are unacceptable on the list, how people ask questions, etc. Participating on a list is not hard but it’s a good idea to make a good first impression.
Many genealogy lists are hosted by Rootsweb. And they are free. You may want to check out the Rootsweb Mailing list page. There are thousands of mailing lists and you are bound to find one or more that fit your interests. There are 2 search boxes and you can search the archives for a name or term of interest. Or search for a maillist (Find a mailing list) by keyword. The keyword Ireland pulls up about 200 mailing lists out of the 30,000 or so lists at Rootsweb.