I'm just glad Abraham listened to G_d when he told him to give Hagar the boot. Imagine stinking arabs being the chosen people!
Well actually, Hagar and Yishmael both eventually did Teshuva - it's some of Yishmael's descendants who are the problem...
And also, after Sarah's death, Avraham ended up taking Hagar back, as a concubine (here she is called Keturah), and she bore him six more children: Zimran, Yokshan, Medan, Midian, Yishbak, and Shuach, whom Avraham sent to the East with gifts. There is a question, though, as to what those "gifts" were, as Avraham gave all of his
property to Yitzchak. (Some say it was a name by whose pronunciation they would be able to perform sorcery - although there is also a question as to whether non-Jews are allowed to perform sorcery.)