I will discuss a couple of recent formal developments in the physics of Euclidean D-branes. In particular, I will discuss the couple of papers arXiv:0711.1430 and 0805.0713 dealing with the interplay between (Pi-)stability for D-branes and instanton induced F-terms. I will also discuss arXiv:0806.2291, which gives some open string interpretation, in terms of non-compact D-instantons, of some entries in the AdS/CFT dictionary for dibaryons.