Partycar!
Tired of battling the 101 on your local corporate shuttle, or, god forbid, in your own car? Then hop the partycar yo! It's the southern-most bike car on the 17:46 caltrain (mt. view). A sociable bunch will usually be on board sharing a few brewskis and snacks. You'll get to 4th/King SF stop at about 18:40.
For Google-types and others in the area, the most common meetup point is the green path at the corner of Shoreline & Shorebird (south-bound side of Shoreline) at 17:17 exactly. The famed and revered "grassy" knoll at the corner of Charleston & Huff is still sometimes used (with a 17:10 departure), but mostly deprecated due to Google's unending expansion. From there we ride to the Jane's Beer (or whatever) on Villa and buy some beers & whatnot.
- train: #311
- departure time: 17:42 (mt. view station)
- beer: yes
- snacks: yes
- mirth: yes
- arrival in SF: ~18:40
Once in SF, it is not unheard-of to gallyvant over to Bender's and continue the merriment. They have indoor bike parking, delicious fake fish tacos, and a strong selection of beers on-tap.