virustotal apps, secunia psi & filehippo updater
1) VirusTotal.com - the uploader and browser extension tools
right click on any file (up to 20mbytes) - send to - virustotal
will scan that file with all their installed antivirus programs
the browser extension helps with scanning unknown links, scans downloads before saving the file, and so on...
btw, i chose not to use the browser extensions, i don't want too many addons in firefox, i'm only using the uploader app.
2) filehippo's update checker and Secunia PSI
these two complement each other quite well. Sometimes (*ahem*... often) PSI lags a bit on the detection of the latest version available but filehippo's manual tool picks it up.
PSI is best to leave running all the time in the tray since it can auto-update quite a few odd programs (irfan view, adobe flash..), prompt the user for updates for other programs that cannot be auto-updated (no silent install available for them: winamp, vlc,..).
PSI will also warn about end of life programs - programs that their producer has decided to no longer support because newer versions are available - such is the case with sysinternals' registry monitor and file monitor that have been retired and replaced by process monitor.