DMOZ listings can do wonders for your website if you are targeting rankings within a specific geographic location or country listed under DMOZ.

Yahoo directory is also nice, but you need to make sure that your website gets listed on the first page of the category. If you are paying $299 and your link gets embedded in deep pages 5-6, then it wont help you much.

As far as edu and gov links are concerned, they receive priority by both Google and Yahoo.

Wikipedia on the other hand uses a section "external links" where you can submit some useful articles from your website. However you should try to submit only relevant and useful articles.