TortoiseSVN 1.6.10 Which means it is completely free, including the source code. But just in case you don't know the GPL too well: you can use TortoiseSVN to develop commercial applications or just use it in your company without any restrictions.
all free|download|programs|software|Anti-Malware|Audio and Video|Browsers and Plugins|CD and DVD Tools|Messaging and Chat|System Tuning|Compression and Backup|Photos and Images|Office and News|Networking and Admin|Drivers|File Sharing|