Unable to connect from one computer, tried many browsers.

I am unable to connect from my Linux workstation - this just began 2-3 days ago, after months of normal behavior. Every other website works well, including blog.plurk.com. Also, other computers (Mac OS X) in the house do NOT have this problem. I've tried many browsers - Firefox, Opera, Konqueror, and even curl, and the same results every time. It is not a DNS problem, because I can traceroute just fine. It appears the web server is not responding to SYN_SENT from this machine.

Here is a traceroute snippet:

8 tge6-1.ar2.sjc1.us.nlayer.net (69.22.143.161) 16.438 ms tge3-1.ar2.sjc1.us.nlayer.net (69.22.143.153) 16.667 ms tge6-1.ar2.sjc1.us.nlayer.net (69.22.143.161) 14.965 ms
9 ae0-60.cr1.sjc1.us.nlayer.net (69.22.143.117) 14.622 ms 15.082 ms 14.707 ms
10 xe-2-1-0.cr1.ord1.us.nlayer.net (69.22.142.57) 91.463 ms 65.468 ms 65.313 ms
11 tge6-4.ar1.ord1.us.nlayer.net (69.31.111.134) 64.799 ms 64.805 ms 64.795 ms
12 as32748.tge8-4-116.ar1.ord1.us.nlayer.net (69.31.111.34) 64.334 ms 64.338 ms 64.852 ms
13 ip17.208-100-32.static.steadfast.net (208.100.32.17) 63.653 ms 63.053 ms 64.061 ms
14 ip247.216-86-152.static.steadfast.net (216.86.152.247) 64.865 ms 64.990 ms 71.768 ms

and some netstat output showing the hang on SYN_SENT:

tcp 0 1 192.168.1.102:53417 216.86.152.247:80 SYN_SENT
tcp 0 1 192.168.1.102:45103 216.86.152.247:80 SYN_SENT
tcp 0 1 192.168.1.102:53410 216.86.152.247:80 SYN_SENT
tcp 0 1 192.168.1.102:45105 216.86.152.247:80 SYN_SENT
tcp 0 1 192.168.1.102:53413 216.86.152.247:80 SYN_SENT
tcp 0 1 192.168.1.102:53414 216.86.152.247:80 SYN_SENT