This is an extension to ESRI ArcView 3.x for cleaning the topology of polygon shapefiles:
Truncating Coordinates of polygons can repair several errors or prevent their occurrence. Multipart Polygons can be exploded into multiple single polygons (records). Incorrect Polygons are cleaned with the maximum settings of ArcView (checking intersections, grain direction and overlapping rings). Overlapping Areas can be identified and removed easily. The overlapped areas are stored in a separate shapefile whereat the visibility of the polygons is considered. Sliver Polygons are very small or thin polygons. They can be removed by appending them to adjacent polygons with several methods (area, border length, enclosed area or angle). Gaps between polygons are empty areas that are surrounded by polygons on all sides. You can easily fill thin or small gaps with different methods (like above). Hidden Gaps are a kind of inversions or indentations in marginal polygons that are closed at a single point. As there are no adjacent polygons normally no gap is found. Zero Point Vertices (at coordinate 0/0) occur due to calculation errors in ArcView when intersecting polygons. They are noticeable as narrow stripes that run out of the theme. Fuzzy Vertices are slightly displaced vertices in the contours of adjacent polygons (the borderlines are not identical) and cause tiny little gaps and overlaps.

The trial version is restricted to the first 400-600 polygons of the theme.

Find out all the details by reading the product documentation here.

GIS software extending the functionality of ESRI ArcView 3.x.
Several extensions are available. More Information