Though weblogs are the perfect example of periodical publications, in many countries they are not liable for ISSN codes. After the Spanish standards organisation denied an ISSN request, a group of bloggers created the IBSN, the Internet Blog Serial Number.
In a short time an IBSN wiki was created and of course there is an IBSN weblog. And finally a handy PHP scripter created a tool to manage all IBSN numbers.
Since I support their cause and because you can never have enough buttons and banners on your weblog, I requested an ‘official’ IBSN code for Brain Tags: