The dangers of doing internet banking from a public computer is highlighted in this news report from IOL:
The Scorpions are investigating an international online banking fraud ring and have already arrested a South African in the case, it was revealed on Wednesday.

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It is thought the man used the spyware on vulnerable computers in internet cafes to capture details including card numbers and customer-selected PINs and passwords.

The details were then transmitted via a remote internet access device to a file server in Estonia, and were then retrieved by the alleged fraudster, who use them to log onto internet banking sites and make numerous electronic fund transfers and prepaid airtime purchases.

Most of the affected internet cafes are in Johannesburg's northern suburbs and Pretoria, with isolated cases reported in Cape Town.