Visual SVN is not free. it need licence for use. AnkhSVN
http://ankhsvn.open.collab.net is der which is seems to be good. TortoiseSVN and TortoiseCVS also does good..
just some info
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TortoiseSVN, a good Windows Explorer extension, despite it's lack of support of Unicode support in any of its Diff tools.
http://tortoisesvn.tigris.org/download.html
AnkhSVN -not a true SCC plug-in, instead works as an add-in, but has much better functionality that the other couple of SCC controls that I've tried.
http://ankhsvn.tigris.org/
SVN Explorer - pretty basic tool, but at least provides a stable Explorer-like stand-alone repository explorer.
http://kafana.org/SvnExplorer/
WinMerge - an excellent freeware open-source file Difference viewer, and merge tool WITH unicode support (use the WinMergeU.exe file).
http://winmerge.sourceforge.net/downloads.php
imageDiff - good free tool for comparing two images for changes.
http://www.download.com/ImageDiff/3000-2192_4-10401779.html. Note: connects to the internet to display ads in a pane at the bottom, but if you use Zonealarm, then disable Internet access, whilst allowing access to the trusted zone. This prevents the program from freezing, without allowing it to display ads.
Finally - WebReports8, another VSS.NET add-in. I haven't actually finished trying this, but it has some nice features. You'll have to re-compile it with the "_scc" option. See here
http://www.codeproject.com/dotnet/file_diff_and_webreports.asp#xx1167087xx read the details on the modification that needs to be performed, then scroll up to the main article)