No, seriously, don't write your own. The following list is comical. Nobody needs another "utility library" dependency.
- access - Access is a library to ease getting and setting values in nested dictionary-like objects by providing a unified interface to hash-tables, clos-objects, plists and alists
- Alexandria - Alexandria is a collection of portable public domain utilities
- arnesi - arnesi is a collection of utilities written by Marco Baringer
- aromyxo - aromyxo is Lars Rune Nøstdal's utilities library
- bknr-utils - bknr-utils is a collection of utilities for bknr
- ch-util - Cyrus Harmon's Cl utilities
- cl-configuration - CL-CONFIGURATION is a package that provides a macro (DEFCONFIGURATION) which can be used to set up various logical pathnames in an elegant way
- cl-jpl-util - cl-jpl-util utilities library required by jpl-queues
- cl-mop - Basic tools to make dealing with CLOS easier and portable
- cl-utilities - A library of semi-standard utilities
- CLLIB - CLLIB is a varied collection of Common lisp tools and routines in CLOCC
- common-idioms - common-idioms is a set of utilities that Brian Mastenbrook uses frequently during his development
- de.setf.utility - de setf utility is a collection of Common Lisp utilities functions and several purpose-specific libraries
- dso-util - A small set of utilities, functions and macros, by David Owen
- fare-utils - fare-utils is a collection of utilities from Fare Rideau
- Formlets - This package implements self-validating formlets for Hunchentoot (it assumes cl-who)
- fukacl - Eitarow Fukamachi's experimental Lisp utilities
- hu.dwim.util - A collection of utilities used mostly by the libraries at dwim dot hu
- incf-cl - (INCF CL) is a collection of utilities
- JARW - Dr John AR Williams' utilities
- kmrcl - KMRCL is a collection of utilities used by a number of Kevin Rosenberg's CL packages
- mccme-helpers - Yet another set of utilities functions
- metatilities - Everyone needs their own set of utilities..
- metatilities-base - Everyone needs their own set of utilities..
- monkeylib-utilities - monkeylib-utilities are Peter Seibel's utilities
- mop-utils - MOP-utils is a small library of utilities for the MetaObject Protocol
- my-util - Tomoyuki Matsumoto's common lisp utilities
- pergamum - pergamum is a collection of small utilities by Samium Gromoff
- qtility - QTILITY is^H^Hwas Robert Smith's utility library, to be superseded by Alexandria
- rutils - REASONABLE-UTILITIES (RUTILS) is yet another general purpose utilities package for COMMON-LISP
- s-utils - Utilities by Sven Van Caekenberghe
- SCLF - SCLF is Walter C
- umpa-lumpa - Umpa-Lumpa is a set of utilities used by armish and liards
- YTools - YTools is a set of utilities that enhance or replace many Lisp facilities, such as the awful 'loop' and the hideous 'format'