Zendesk releases a free plan

This reminds me of my favorite Usenet Oracle where all the upgrades give you what you assumed you already had with the lower account:

  The Usenet Oracle has pondered your question deeply. Your question was:

   > how do i switch to using netscape browser with my pipeline account?

  And in response, thus spake the Oracle:

   }       Thank you for your question.  As your Internet Service Provider,
   } we are pleased to assist in your exploration of the computing world's
   } fastest growing realm.
   }
   }       As you have no doubt observed, the explosion of the Web has made
   } your existing command line account rather limited.  To better serve
   } your expanding needs, we are pleased to offer the following tiered
   } service packages:
   }
   } Baseline Account
   }       This is our most basic account.  You get a shell prompt.  On-line
   }       help is disabled.  Transfer protocol is 'cat'.
   }       $5.00/month
   }
   } Extra(tm) Account
   }       All Baseline features, plus:
   }               o On-line help
   }               o On-line manual pages (first 20 accesses free)
   }               o XModem (checksum)
   }       $7.50/month
   }
   } Super(tm) Account
   }       All Extra(tm) features, plus:
   }               o Unlimited manual page reference
   }               o Lower case support
   }               o 8-bit connection
   }               o XModem (CRC)
   }       $10.00/month + $1.00/hour
   }
   } SuperExtra(tm) Account
   }       All Super(tm) features, plus:
   }               o Command line editing (backspace, ^X)
   }               o 24-hour access privileges
   }               o XModem (1K blocks), YModem
   }               o Free outbound mail
   }       $12.00/month + $1.25/hour
   }
   } Master(tm) Account
   }       All SuperExtra(tm) features, plus:
   }               o Free inbound mail
   }               o Newsgroup access
   }               o ZModem
   }       $15.00/month + $1.65/hour
   }
   } MasterExtra(tm) Account
   }       All Master(tm) features, plus:
   }               o Configurable newline termination
   }               o Apple Newton(tm) support
   }               o Personal netnews killfiles enabled
   }               o 9600 bps access privileges
   }               o Kermit
   }       $20.00/month + $2.10/hour
   }
   } MasterSuper(tm) Account
   }       All MasterExtra(tm) features, plus:
   }               o Account password protection
   }               o Shift-lock support
   }               o Access to code development tools (vi, emacs, EDLIN,
   }                 etc.)
   }               o UUCP
   }       $22.00/month + $2.50/hour + $0.01/Kbyte
   }
   } MasterSuperExtra(tm) Account
   }       All MasterSuper(tm) features, plus:
   }               o Access to additional code development tools (cc, as,
   }                 etc.)
   }               o 80 column support
   }               o 512K storage
   }               o Tint control
   }               o Gopher
   }       $25.00/month + $2.75/hour + $0.05/Kbyte
   }
   } Executive(tm) Account
   }       All MasterSuperExtra(tm) features, plus:
   }               o Access to compiled output (a.out)
   }               o 2048K disk storage (additional to 512K on tape)
   }               o 600 DPI
   }               o SLIP/PPP
   }       $50.00/month + $4.99/hour + $0.198/Kbyte
   }
   }       We are also pleased to announce our first account specially
   } tailored for businesses:
   }
   } Entrepreneur(tm) Account
   }       o Your choice of shell (csh, tcsh, ksh, bash, etc.)
   }       o SLIP, PPP (yielding direct FTP and HTTP connections)
   }       o 14400 bps, 28800 bps, ISDN, or leased line connections available
   }       o 20M storage on RAID array with mirrored backup (additional
   }         storage for extra charge)
   }       o Full suite of development tools (yacc, lex, sed, awk, perl,
   }         etc.)
   }       o DNS registration (become your own domain on the net!)
   }       o Complete PGP tool set
   }       o CNID reverse-lookup phone database
   }       o USGS maps collated and annotated by zip code and demographics
   }         (in Postscript and DVI)
   }       o Access to all our members' registration data (excepting those
   }         who explicitly requested at least three times to be excluded)
   }       o Public relations tools (SpamTool, with NoCem evasion heuristics)
   }       o Libel/slander control facilities (canceltool)
   }       o Intelligent mail filter suites
   }       o 24-hour phone support
   }
   }       $300.00/month!
   }       (Must be registered as a commercial business within your state to
   }       qualify)
   }
   }       We think you'll agree these new options offer unparallelled
   } flexibility, and that no one else offers a better deal for direct
   } Internet access.  We're pleased you've chosen us, and hope will
   } continue to stay with us.  See you on the Net!
   }
   }       You owe The Oracle an account on best.com.

From http://www.zendesk.com/product/compare it seems that SSL encryption is provided on the starter plan. Only hosting of an ssl certificate for custom domains isn't, which seems fair.