Submission of blog links is essential to increase the outreach of your website/blog. Submission of blog links is different from link exchange since you submit your URL to those website which accepts links from others as well. So ultimately it does not become a link building exercise but rather that of content exchange. It also becomes a meeting place for bloggers or people with like minded interests. Facebook is perhaps the most popular link submission platform of recent times.
What is a submission of blog links
A webmaster or admin opens a page or a post announcing the acceptance of links for a particular theme or a topic. Members or guests accordingly post their links in the main post or the comments. Technologies like Inlinkz has helped simple blogs to run attractive link submission campaigns or contests.
Where to submit links
From a simple google search to following fellow bloggers to see which contest they are taking part, search for link submission is a long process. It is also a good idea to check if the website is active or not before submitting your link. The more number of participants, the better and safer it is. Remember it is not a link building exercise and do not go overboard with it. At least here, the big daddy is watching. Blog directories have been deliberately left out.
Websites for general purpose link submission
Websites for submitting photograph URLs
Please contribute in comments to expand the list.