Extending virtual screening approaches to deal with multi-target drug design and polypharmacology is an increasingly important aspect in drug design. In light of this, the concept of accessible chemical space and its exploration should be reviewed. The great advantages of re-using drugs with safe pharmacological profiles with favourable pharmacokinetic properties highlights drug repositioning as a valid alternative to rational drug design, massive drug development efforts, and high-throughput screening, especially when supported by in silico techniques. Here, we discuss some of the advantages of multi-target approaches, and we review some significant examples of their application in the last decade to that well known class of pharmaceutical targets, the G-protein coupled receptors.