I think everyone has his guilty pleasure which you wouldn't recommend wholeheartedly to your friends. Mine's is definitely Obsidian's spy-RPG Alpha Protocoll. I personally enjoyed it very much even though it's a wobbly, inconsistent game that gets a few things right. It's filled with so many awkward and glitchy bits you get the feeling that it should've spent way more time in development. If you thought shooting in Mass Effect 1 was imprecise, Alpha Protocoll's is even worse. But I adored the game nonetheless because of its nonlinear storytelling and the possiblity of influencing the personality of the protagonist through decisions. Thank you Obisidan.
I just started playing this, and it's definitely a gem in the rough.
I remember playing through the game at least 6 times, Alpha Protocoll is not a very long game, and every time I experienced scenes I hadn't seen before because of different decisions I made. You can compare it somehow with The Walking Dead, the only difference is, it tried to be a game and failed terribly at that. However, if you belonged to those guys who complained about Mass Effect's decisions being without consequence in the end, Alpha Protocoll gives you real freedom of choice. You have of course the grand narrative, but it's up to you to decide how the story evolves. The game lets you not meet certain characters in one playthrough for instance, in another one you're able to meet them because you made different decisions. This is really rare in a game and I haven't played anything like it before. The ending you get is ultimately the sum of the actions. For all this reasons I'm willing to forgive the game's striking glitchiness and lack of polish.