Back in my early days of gaming, aside from AD&D, I had three basic "go to" RPG systems:
All had their own things going for them. What I liked about RuneQuest, besides the awesome setting and supplements, was the comforting familiarity it had in many ways to D&D - and then ran off in a totally different direction.
OpenQuest is, in my eyes, a direct descendent of that old Chaosium edition of RuneQuest. Even better, OpenQuest Basic is free. It's derived from the Mongoose RQ OGL.
And yes, Legend (the latest version of the Mongoose RQ OGL) and RuneQuest 6 Essentials are also available, at a buck and PWYW respectively.)
The Minotaur for Old-School Essentials
*Requirements:* Minimum STR 9, Minimum CON 9
*Prime Requisite:* STR and CON
*Hit Dice:* 1d10
*Maximum Level:* 8
*Armor:* Leather, including shield...