Altmetrics

Indexes and provides citation counts for a wide range of scholarly publications that may not be included in other databases (including theses, books, reports, conference papers, posters and patents).
Set up a free Google Scholar Citations profile which automatically graphs citations to your works over time, and calculates h-index and i10-index.

Summarises recent citations to publications to provide a number of lists including:
Top 100 publications by language, and
Top 20 publications by research areas and specific subcategories. Access is free.
It displays the h5-index and the h5-median for each included publication.

Free downloadable software that retrieves Google Scholar and Microsoft Academic Search data. It provides many metrics for your search results including the total number of papers and citations, average number of citations per paper, average citations per author and paper, Hirsch’s index and related metrics, Egghe’s g-index, an age weighted citation rate.
It also provides tools to look at author level impact and co-citation analysis.

A free tool for citation analysis (based on more traditional metrics but including more research outputs than just journal articles). It works as a browser extension that supports Firefox and Chrome to provide an interface for Google Scholar data. It provides similar functionality to Publish or Perish and impact data can also be published as linked data.
You can also explore information on the Scholarometer website including top authors, discipline statistics and author networks.
You just need to download the browser extension to get started.