Sales of new Wi-Fi mobile handsets that use Skype Ltd. software and do not require a PC to make calls are gaining momentum ahead of the holidays, companies report.

The Wi-Fi mobile phones are rousing interest for two reasons: the low cost of using Skype services to make calls, and because people can use them more like a traditional mobile phone, without the aid of a PC. Skype, for example, is offering the WSKP100 by SMC Networks Inc. in a package on its Web site that includes the handset, a Wi-Fi router, 500 minutes of calls to regular mobile phones and landlines (SkypeOut) and 12 months of Skype voicemail for just