FoxitReader (www.foxitsoftware.com)
Foxit Reader is a free PDF document viewer and printer, with incredible small size (only 2.1 M download size), breezing-fast launch speed and amazingly rich feature set.

PrimoPDF (www.primopdf.com)
Convert Word, Excel, and other printable file types to PDF.

TrueCrypt (www.truecrypt.org)
Free open-source disk encryption software for Windows.