describes itself as a Free Social Media Search Engine and it's been around for a while; in fact I blogged it back in August of 2012 and thought favourably of it. It's now undertaken a really massive overhaul, and it's entered my list of 'social media search engines to watch'. You can use it without registering, but if you register, you can save your searches. Results are in three columns - Facebook, Twitter and Google+ - I haven't seen any other search engines give content in that mix before, and I found the comparision element really useful.
However, there is a lot more useful material than just recent postings. There's a helpful analytics section, with sections on sentiment, users, domains, types of post, keywords, popular results and much more besides. It does seem to have a few bugs - it didn't want to search for #hashtags - or if it did, it took so long I wasn't waiting any longer, and some of the results seem to be incorrect, but that could easily be because the tool they're using (eg Facebook search) is the one failing, not them.
In summary, it's a good addition to the collection of social media search engines out there, and worth a look.