One of our recent papers is listed in Top 20 Most Downloaded Articles in PoF (October 2007): http://scitation.aip.org/dbt/most_downloaded.jsp?KEY=PHFLE6&agg=md Mixing enhancement behind a backward-facing step using tabs Hyungmin Park, Woo-Pyung Jeon, Haecheon Choi and Jung Yul Yoo Phys. Fluids 19, 105103 (2007)