To unzip all zip files in a directory
This won't work:
unzip *.zip

Escape the *:

unzip \*.zip

Use the -d flag to extract files into exdir

To unzip multiple zip-files and recurse to lower directories. Extract each zip to the directory it is in.

for i in `find . -name "*.zip"`; do unzip -d `dirname $i` $i;done;