Free directories are perfectly fine for SEO, unless you spam.

Some of the best free directories include DMoz (biggest one ever, takes eons to get approved though), Technorati, and Boing Boing.

Please submit manually and do NOT over squeeze your keywords into the descriptions or tags. Do not submit too many, say 1000 in one day with a software. You'll get slapped by Google instead.

In fact, 20 submissions should suffice.

Get your directory list from a good source like this one that has been doing it for more than 10 years
Free Directory List - SEO Friendly - Info Vilesilencer
Avoid auto submission tools or paying services to list you in directories.

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