Aaron Bertrand (@AaronBertrand) shows some tricks for getting row counts efficiently, and explains why an accurate row count for a large table is a pipe dream.
Paul Randal (@PaulRandal talks about Page Life Expectancy – what it is, why fixed thresholds are meaningless, when it matters, and what you can do about it – in this latest installment of his "knee-jerk troubleshooting" series.
Aaron Bertrand (@AaronBertrand) demonstrates an affordable approach to readable secondaries, without the need for Availability Groups and all the licensing costs involved with Enterprise Edition and Software Assurance.
Paul White (@SQL_Kiwi) demonstrates performance tuning a SQL Server execution plan as a whole, instead of honing in too narrowly on individual operators.