Same conjugation as κολυμπάω/κολυμπώ.
Also, I think you mean έχω and not έγω (which I think does not exist; you may be confusing it with εγώ).
And είμαι is irregular; I don't think any other verb conjugates quite like it.
There are a fair number of verbs in -άω.
All mean horse, the differences are: the first is the standard word used in both formal and informal contexts, the second is a bit more formal and is used in specific contexts (e.g. the Trojan horse is o Δούρειος ίππος, never άλογο, or for horsepower/ιπποδύναμη something is __ ίπποι but could be άλογα) and for compound words like ιπποδύναμη, the third is a poetic form.