A borehole log (those we were using were generated with Gint) is basically a table of values.
Convert the log into a table that contains coordinates (X,Y) of the hole location, Surface Elevation, Depth (top of sample), Bottom (depth of sample), and other attributes you will need. (You can probably write a VB procedure to streamline this part.)
Convert this table into a 2D point feature class (XY Event layer -> Export to Feature Class)
Create a UIButton and connect it with the attached VBA procedures. (Not tested in about 2 years. Hopefully I've included everything)
You might need to add all the needed references to VBA.
There is an exaggeration option as well. A message will pop up asking you if you which to exaggerate the vertical lines. I did it because i did not want the surface the be vertically exxagerated but wanted the holes to be.
It basically creates 3D lines from coordinates starting at the top and subtracting the depth of the samples. It does not support inclination or deviation only because when I wrote it we only dealt with vertical BH, MW.
My drillholes are now a lot more complicated (mining) so every one is deviated and inclined in various directions. I have not use the script in a long time as it does not fulfill my needs. You can probably use any decent drillhole management software to handle your borehole logs as long as you have them in an excel/table format and they contain X,Y,Z values and depth of samples at minimum. This type of software also handles deviated and inclined holes so long you have the drillhole survey data. (azimuth, dip, etc.)
I've personally only used GEMS by Gemcom (very expensive), Target by Geosoft and Target for ArcGIS. The Target for ArcGIS is an ArcGIS Extension and it comes with a voxel grid functionality and 3D visualization capabilities but I use the standalone version because there were some limitations with the extension. The extension is about $2500 and the standalone version about $6000. I hear that Leapfrog Hydrology/Mining can also do this although it is meant mostly for 3D visualization (it's also very expensive but it is suppose to be the absolute best tool for rapid 3D visualization of subsurface geology / hydrology drillholes and wells. etc. - not personally tested but have the license on my desk) And of course you can export the results of any of the mentioned software into a format compatible with ArcGIS / ArcScene.