The lists with links at the bottom is becoming a bit long so I am going to create some pages with specific links I want to remember or share, for one reason or the other. I haven’t gotten far yet, but more will come:
R tips & tricks – list with links to web pages containing tips in using R I have needed at one point in time and may need again, i.e., a personal set of links I want to remember.
My list of software – Some links of software I am using or have used in the past and would recommend.

Hi, I’m a biodiversity scientist working in Southern Africa. I’ve migrated from PC to MAC and am looking at open source software alternatives. I’m looking at GRASS as an alternative to ArcGIS, mainly for heads-up digitizing from airphotos and modelling species distributions and diversity. Your site shows that there is an interested community out there. Thanks
Your welcome, I am sure you will find there are many very good open source software alternatives (I have no experience on the MAC, but both on Windows and Linux I use mostly open source software). GRASS GIS is a great and very powerful GIS, especially for work on raster. In combination with R, it is a very powerful tool for species modeling. The digitizing module is very good in enforcing a proper topology. On the other hand, it is not the easiest tool available. They are currently working on a new and very user-friendly digitizing module, but for now you’ll have to work with the older module which can be a bit cumbersome to learn. As an alternative you might want to try out the digitizing tools in QGIS. Try out the native QGIS digitizing tools and the digitizing tool in the GRASS toolbox and see if these fit your needs. The latter is easier to use in my opinion than the one implemented in GRASS itself.