Patty Jensen has been working her proverbial off recently with a series of posts about slushing for ASIM, using examples to highlight the biggest problems with each of the volunteer submission texts.
This is a fantastic way to see fifteen different story openings and the ways they worked or didn't work, and even chat with Patty further about the issues involved.
ASIM pre-slush workshop redux � Must Use Bigger Elephants
Patty's blog is also an excellent one to have bookedmarked for further reading. She also explores issues of Science in SF, researching, publishing, and short fiction. She also works tirelessly for ASIM.