I typically avoid the vendor-specific certifications and stick with industry standards. You can't go wrong having the CompTIA certifications on your resume. The only vendor-specific certification I'd ever go for would be Cisco. Right now, I wouldn't bother since it doesn't apply to anything I'm currently doing and I don't have any Cisco equipment in our current IT environment.
I'm currently experimenting with a couple of Mikrotik routers, anyway... The RouterBoard 450 to be specific. Our generous web-hosting company suggested these in lieu of using Cisco; something they've been using for several years now.. The price is right - $69.00 for the board and RouterOS license - and they do just about anything you could possibly want. I may look at one of their wireless solutions for this summer.
Anyway, I'm way off topic now. I did the CompTIA A+ and Network+ a few years ago. After those were out of the way, I did the Server+ and Linux+, just for the heck of it!
I'd like to do the LPI, someday. Maybe when things slow down (ha!)...