Bitcoin SMS Alert
Bitcoin SMS Alert is a Windows based PC application that sends SMS text alerts directly to a user's phone. The current version obtains price information using API's from either MtGox.com or BitcoinCharts.com in three different currency denominations (USD / GBP / EUR), and will alert the user if price and/or price percent changes have have exceeded a given upper or lower bound. Other features to prevent too many text alerts, and different update intervals are included as well.
Description:
Unlike some other monthly services that exist, this program costs only a one time fee of $2.99 USD payable via MtGox instant BTC checkout. Updates are provided free of charge if an e-mail address is supplied upon checkout. The author claims that custom tweaks / upgrades can be made for small donations.
Current Version: v1.1 (Made available on August 28, 2012)
More information and a video demo can be found on the website.