There's no substitution for a quality antivirus solution, but how many times were you in a situation that you simply have none at your disposal? In such situation, the best you can do is use something that's free and fast. We bring you a list of online virus and malware scanners which will do just fine for a quick scan of the system.
Avast - Online version of popular antivirus software Avast will scan individual files of up to 512kb in size.
BitDefender - An online version of the BitDefender software. Will scan your drives, files, and boot sector. Works only with Internet Explorer.
Computer Associates Malware Scanner - Browse your drives for a file you suspect of being malware and upload it for their scanner to check it for you.
Eset - Just simply click their terms of service and scan your entire system for occurrences of malware.
Freedom - Chck all of your storage inside your browser with this tool based on F-Port.
Jotti's Malware Scan - Uses several scanners at once to scan files that you upload to detect malware that may be hidden.
NanoScan.com - Requires a small download and then accesses a constantly updated database of known threats. Extremely small an fast.
Panda Security - Searches your system for worms, viruses, trojans and more after a small Active X download.
TrendMicro - This service will not only scan for viruses, but also spyware and malware.